'America's Test Kitchen' On Grilling Peaches, Tofu And Burgers

Transcript

TERRY GROSS, HOST:

This is FRESH AIR. I'm Terry Gross. I'm not much of a cook, but I love talking about food with Bridget Lancaster and Jack Bishop of the Public TV series "America's Test Kitchen." When they talk about preparing food, they're really good at explaining why the recipe works. Bishop is the editorial direct of America's Test Kitchen. Lancaster is the lead instructor of its cooking school. They contributed to the new "DIY: Do It Yourself" cookbook, which Jack also co-edited.

They're going to talk about preparing summer foods, and then they're going to answer some cooking questions from the FRESH AIR staff. Bridget Lancaster, Jack Bishop, welcome back to FRESH AIR. So let's start with a good way to make fruit last a little bit longer by making an easy refrigerator jam. And I'm assuming a refrigerator jam, it's not like a canned jam. So it's not going to last for a really long time on your shelf, it's going to last for, what, a few weeks in your refrigerator?

BRIDGET LANCASTER: Yeah, that's right, probably up to three weeks at the maximum. And, you know, I think a lot of people don't know that they can make jam very easily and just store it in the fridge. You don't have to make a huge batch and can it to preserve it for months and months. The refrigerator...

GROSS: How easy is it?

(LAUGHTER)

LANCASTER: If you can boil some fruit, you can pretty much make refrigerator jam. Basically, it's, you know, you can use raspberries, strawberries, blueberries with sugar. It's usually - for strawberries it's roughly a pound and a half of strawberries that you've hulled and cut up into chunks, and then you mix it with a cup of sugar, a little bit of lemon juice. You bring all of that up to a boil, and then you mash the heck out of it with a potato masher.

And this does a couple of things. It - the boiling very rapidly helps to release some of the pectin, the natural pectin in the fruit. So you don't need to add any of the boxed liquid or powdered pectin, which is a natural thickener found in some fruit. But also the mashing helps to release that and gives it that nice, course texture.

But all in all, you're cooking this for about 15 to 20 minutes on the stovetop. You can check it...

GROSS: You're boiling it that long?

LANCASTER: Yeah, yeah, boiling it for about 15 to 20 minutes. It's actually pretty quick-cooking compared to a lot of jams, which will call for cooking for 30 minutes or more to really reduce down to a jammy state. So after about 15 minutes you can check to see if it's done.

And there's a really cool trick, it's kind of an old-fashioned trick, where you take a metal spoon and put it in the fridge for a little while, maybe 10 minutes so it gets super-cold, and then you dip it into the hot jam mixture and see if it all comes off the spoon in one big clump, and you know it's going to be thick enough after it sets up.

And so after it's done, and you've figured out that it's at the right thickness, and it's not going to be too thin later on, you can just put it in a container, a nice glass container is great, cool it down to room temp and then cover and then try not to use it in the first few days, but it'll keep up to three weeks.

GROSS: Don't use it in the first few days?

LANCASTER: No, you try not to use it all in the first few days. That's the problem, you just want to...

GROSS: Oh not to use it all, oh, because it's so good.

(LAUGHTER)

GROSS: OK.

LANCASTER: It's just so much fresher than the really long-cooked jams. And since you can make a little bit of it, you don't mind doing it more often.

GROSS: So that chilled spoon, is it in the refrigerator or the freezer?

LANCASTER: You can put it in the freezer, it's best, and it's a great little trick because, you know, I don't know if you've ever made jam, and you go, and you let it cool down, or you can it, or you put it in a container, and then you go to use it after it's all cooled down, and it's still too thin. But this, you know, makes it so that you can predict the thickness after it's cooled down.

So you just take that frozen spoon, dip it in the hot jam mixture, and it'll cool it down instantly so it should come off in one sliding clump.

GROSS: A lot of people have a whole lot of tomatoes because many people who have any kind of garden at all have tomatoes in it, and then they give some to friends, and there are still plenty left.

(LAUGHTER)

GROSS: So do you guys have a good tomato recipe to make the tomatoes last?

JACK BISHOP: I love to oven-dry them. So this is - you know, if you love sundried tomatoes, this is a little less dried than that. So it's a little closer to fresh, a little juicier by oven-drying them, but the idea is the same is that you're basically dehydrating the tomatoes and concentrating their flavors.

And it's - this recipe is really best with a meatier tomato. So if you are growing a lot of plum tomatoes or some of the heirloom varieties that are really meaty rather than juicy, it's very, very simple. You simply cut the tomatoes. If it's a plum tomato, you take the core out, cut it in half, put it cut-side-down on a wire rack inside a baking sheet.

And in order to make cleanup easier, often we'll put some foil on the bottom of the baking sheet. And the wire rack is going to promote nice air circulation when this gets into the oven. And you can toss - you should toss them with some salt and pepper and some olive oil. If you want to add some herbs, herbs de Provence is really nice because that's lots of herbs all in one mix, and it's dried. It has lavender and fennel and thyme. But you can use whatever herb you like.

And we start out in a hot oven, so it goes in at 425 for 20 minutes, and the idea is that will blister the skin, and then you can come back about 30 minutes later, 20 minutes later when the skin is blistered, and peel off the skin with a pair of tongs. So rather than having to individually peel the tomatoes by hand, you're letting the heat of the oven do that.

And then once you've taken those skins off, you put the temperature down to 300. So it's basically really drying rather than roasting the tomatoes and let it go for three or four hours. You know, when it's kind of brown around the edges and shriveled, you can taste them. They are done. And then you put them into a clean container, cover them with olive oil, and you've got them probably for about three weeks that they will last in the refrigerator.

I put them on sandwiches, slice them and put them in sandwiches, salads, make a mayonnaise with them. It's really great to puree. You can sort of dress up some Hellmann's or Kraft with freshly oven-dried tomato is a really great, you know, accompaniment for a piece of fish or sandwich spread. And it's a really simple way to preserve a lot of tomatoes.

GROSS: It sounds good. What's the absolute easier thing to do with a lot of tomatoes?

BISHOP: Well, the easiest thing to do is to slice them, put some olive oil and salt on them.

(LAUGHTER)

GROSS: I knew that.

BISHOP: But we're not - but we're not quite there yet, but I'm with you that at some point you feel like there are more tomatoes than you can possibly eat.

LANCASTER: Yeah, you run out of friends to give them to, basically.

(LAUGHTER)

BISHOP: I think one of the advantages of the oven drying is it allows you to, you know, think about them in ways you wouldn't. But I think my favorite sort of cooked application is to just make a really simple pasta sauce. And I don't really bother with seeding or removing the peels. I feel like I will eat the whole tomato, other than the core. And just chop it roughly, put it into a hot pan with some good olive oil, some garlic.

The secret is to not overcook it. It's a fresh tomato, and so when I see people take a fresh tomato and then cook it for two hours, I don't really understand the point of it. So really five minutes maybe 10, just until the juices are drawn out of the tomatoes, you've added some herbs, salt and pepper, and you have a simple, fresh pasta sauce that is better than anything you are going to make the rest of the year.

GROSS: Oh, that sounds good, and it really does sound easy.

BISHOP: It is really easy, I promise you.

GROSS: Well, thank you for that. So I'm - you know, we're talking about how to make good, tasty and creative use of any extra fruits and vegetables that you're not going to be able to eat fresh quickly enough. So how hard is it to make, you know, a decent pickle out of your extra cucumbers?

LANCASTER: Actually, a lot of people think that making pickles is complicated, and there certainly is the old-fashioned way, which is a naturally fermented cucumber, but - or any other vegetable. But quick pickling has kind of become very, very popular. It's just as easy as bringing up to a boil some vinegar, maybe a little bit of sugar, salt definitely. If you want to steep herbs or any kind of spices in there, you boil the spices or herbs in the brine mixture, kind of the pickly brine mixture.

And then you pour it over your cucumbers, or we have a great recipe for dilly beans. So if you've got, you know, green beans that are, you know, littering your yard, and you can't eat enough of them, it's great for that, too. I use the same method. So you pour it over the vegetables. I use the same method with watermelon rind, as well.

You know, there's - you know, you give you kids, you cut up a watermelon, you give it to your kids, and you're always left with this bunch of rind, and you don't know what to do with it. But the outer rind is actually really like dense cucumber. And to me it's even better than the pink flesh.

So it's the same thing, you chop up the rind after you've peeled off the green part, you bring this vinegar-salt mixture up to a boil, add whatever spices you like, pour it over the vegetables, let them cool down to room temperature, and then those can go in the fridge for a week, maybe 10 days. They get a little bit softer than a traditional pickle, and the vinegar does all the work of making it nice and sour.

But it's so easy. You can pickle just about anything: pickled beets; green beans, as I said; watermelon rind; of course cucumbers. There's bread and butter pickles, which you slice the cucumbers really thin and actually simmer them in the brine before packing them away, so easy.

GROSS: Oh, all right. My guests are Bridget Lancaster and Jack Bishop of the Public TV shows "America's Test Kitchen" and "Cook's Country." They've contributed to a new cookbook, "DIY: Do It Yourself." More after a break; this is FRESH AIR.

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GROSS: If you're just joining us, my guests are Bridget Lancaster and Jack Bishop. They're both with the Public Television shows "Cook's Country" and "America's Test Kitchen," and they've contributed to the new America's Test Kitchen cookbook, the "DIY: Do It Yourself" cookbook. And Jack Bishop is also an editor of that book.

So it being summer and all, ice cream is particularly wonderful. There's a recipe in the new book for, you know, how to really easily make a chocolate ice cream shell. So I'd like you to share the recipe and tell us, like, what's the magic. Like how does the liquid chocolate turn into a nice, you know, crunchy shell?

LANCASTER: And instantly, too, I mean...

GROSS: And instantly, yeah.

LANCASTER: Yeah, that was always one of my favorites memories is we'd go to Dairy Queen, and you would get the cone of soft serve and ask for a chocolate dip, and they dipped it in the mixture, and it went in liquid, and it came out solid with that crunchy, sort of chocolately topping.

(LAUGHTER)

LANCASTER: I would call it a brown topping more than anything. And actually they sell a product at the store, too, that does the same thing. The problem with anything like that is it maybe doesn't have enough chocolate flavor, enough flavor in general for our needs and our desires. But the chocolate ice cream shell, the magic ingredient to that is coconut oil.

Coconut oil is solid. I keep a jar of it in my pantry. It's solid at 70 degrees. At around 74 degrees, it turns to a liquid. So that's pretty much the big secret. So for this particular recipe, we added a little bit of vanilla and some instant espresso and a little bit of salt.

GROSS: So hang on a second, conversely it's liquid at 74, but as soon as it gets to 70, it's solid, so if you put it over ice cream, it's going to like magically transform into solid immediately.

LANCASTER: That's right. So it's liquid as you pour it, so it needs to be above 74 as you spin it onto your ice cream. As soon as that hits your ice-cold ice cream, it is magic in front of your eyes. It sets up. It turns into that crunchy, hard topping that you can crack through with a spoon.

And we dolled ours up. We actually added real chocolate into it instead of just cocoa. So we've got four ounces of semisweet chocolate in that to a third cup of coconut oil. And we just microwaved that together, and then we added in the vanilla, a little bit of instant espresso and a little bit of cocoa powder.

After it's cool for about 30 minutes, believe it or not this will stay on your counter for two months.

GROSS: Wow.

LANCASTER: So in a relatively solid state. So when you've got your ice cream there, and you want to pour some over your ice cream, you just scoop out a little bit into a bowl. You can melt it in the microwave at a nice lower heat. You just want to melt it above, again, 74 degrees, and then you can spoon it over your ice cream. The kids love it. What am I talking about? I love it.

(LAUGHTER)

GROSS: That sounds really good.

LANCASTER: And it's a lot of fun.

GROSS: And you also for summer have a recipe for cold-brewed coffee. What's the advantage of brewing your coffee cold as opposed to brewing it hot and then making it into iced coffee?

BISHOP: It's all about flavor extraction. So when you are using the proper temperature for traditional coffee - it's 205 degree is the ideal temperature to extract all of the flavor compounds relatively quickly. But you get a lot of bitter notes, a lot of those tannins. A lot of people who think they don't like coffee, when they taste cold-brewed coffee, it's a revelation.

And cold-brewed coffee is what it sounds like. You're using room-temperature tap water, and you're using time. So obviously you are not going to have a cup of coffee in two or three minutes if you're using cold water, but if you are willing to give it 24 hours, some people like to go 48 hours, you can - we do a super-concentrate.

So we use way more coffee than you think you would need, and then we will use it in the French press. And so the coffee is in the French press, and it is brewing for 24 hours. You just, you know, put the coffee in, you add the cold water, you want to stir it to make sure the grounds are swollen and evenly hydrated. Then you plunge, and you've got your concentrate, which can go into the refrigerator for several days.

And then you can reconstitute it. It's basically strong enough that you are - when you're ready to make iced coffee, you add one part of this coffee concentrate and one part cold water, or two parts if you want a milder brew, and it's really beautiful, floral, fruity notes of the coffee, none of the sort of heavier bitter notes.

And, you know, you do this with good coffee. I wouldn't do cold-brewed coffee with mediocre, already-ground beans. But if you want to get some nice coffee, an Ethiopian coffee or a Kenyan coffee, which have a lot of those floral, fruity notes, it's just an absolutely great way to appreciate the coffee.

And because you do it in advance, you have iced coffee on demand in your refrigerator when you want it.

LANCASTER: It's brilliant in a vanilla milkshake, too.

(LAUGHTER)

GROSS: Oh nice.

LANCASTER: I've tried it in there, a few spoonfuls.

GROSS: Jack, how often do you make the cold-brew coffee?

BISHOP: I will say pretty much all summer. I've got some concentrate sitting in the refrigerator. I love - I have a cappuccino every morning, but when it - during the summer at lunchtime, I like to have iced coffee. And I'm a very impatient person who does not want to wait for it to cool off. And I also don't want it to be completely diluted.

I mean the great thing about this is a lot of people make hot coffee when they want iced coffee, and then they throw a ton of ice in, and it's kind of basically brown liquid that has a lot of harsh notes. And this is totally smooth. It's a really revelation, and the fact that you can do it in relatively large quantities, you do it, you know, once every four or five days and make enough concentrate that will last for the next four or five days.

And I make coffee once and enjoy it for many days afterwards.

GROSS: OK, so this is - I am wasting this question on people of such talent and expertise as you, and I am showing off my total inexpert abilities in the kitchen, but - so here's my question. I tend to eat out a lot because I'm just so tired after a day's work, and then I have to, you know, I do a lot of preparation at home at night.

But when I do cook, it's - it's not a pretty sight. I mean, like what I tend to do is microwave some chicken breast until it defrosts, and then I microwave the chicken breast. So what's the fastest thing I can do to cook the chicken breast so it's tastier than it would be in the microwave, but I'm not going to, like, totally dry it out?

LANCASTER: Is this a bone-in, skin-on chicken breast, or boneless?

GROSS: No, no, it's just like a chicken cutlet kind of thing.

LANCASTER: Pan saute it.

GROSS: Pan saute it?

LANCASTER: Yeah, just heat up a little bit of oil in your skillet until it's just starting to smoke, medium-high heat. Dry off the cutlets, a little bit of salt and pepper, and, you know, each side maybe, depending on how thick the cutlet is, a minute and a half, two minutes.

GROSS: That's all?

LANCASTER: That's it.

BISHOP: And I'm going to give you an alternative, which is to do en papillote, the French technique, but use aluminum foil, and to simply put the cutlet...

GROSS: En papillote means in paper?

BISHOP: In paper. It's traditionally made with parchment paper, but you can do it with aluminum foil.

LANCASTER: That's called en (French spoken).

(LAUGHTER)

BISHOP: And take the - put them in a single layer. So if you're doing two chicken cutlets, you know, don't stack them on top of each other. I will put some sliced vegetables, juicy vegetables like tomatoes are nice, you can do some zucchini, you could also julienne carrots or leeks, and then put a little bit of fat of some sort, a drizzle of olive oil, a little bit of butter mashed up with some lemon zest and fresh thyme.

Put a pat of that on top, seal it up, put it on a baking sheet, 15 minutes, 400 degree oven, you open it up, and all of those flavors have mixed together. It's kind of look cooking, but you didn't actually touch the food while it was cooking. You just put all the raw ingredients together in the packet and let them sort of co-mingle in the oven until the chicken is cooked through.

GROSS: That sounds really good. I'm going to try that.

LANCASTER: It's great with fish, too, and it creates its own sauce, too. It's really nice.

GROSS: So you kind of put the foil underneath and then pinch it together on top so it makes like a little dome?

BISHOP: Yeah, and you can fold it over. If you're doing it really neatly, you'll do like a sort of square package and fold the edges over very crisply and then fold them again into a sort of nice, sealed package. You might also want to put a splash of white wine of vermouth in there, especially with some fish, I love that. It gives it a little bit of natural juices. Don't go overboard. Like a tablespoon is going to be enough just to get some juices going, especially if you're using like leeks or carrots rather than tomatoes, which are going to create some juice.

And it's just really simple, and just make sure that it's sealed. You know, you can check it with a thermometer if you're worried about the temperature or cut into it, but usually 15, maybe 18 minutes if it's a really thick chicken breast in that foil packet at 400 degrees with some vegetables and a little bit fat. You are going to need to add some olive oil or some butter, but not a lot. A tablespoon is going to be plenty per serving, and it's going to be great.

GROSS: Bridget Lancaster and Jack Bishop will be back in the second half of the show. They're both with the Public TV show, "America's Test Kitchen," and they've contributed to the new America's Test Kitchen "DIY: Do It Yourself" cookbook. Three of the recipes they discussed are on our website: oven-dried tomatoes; sour dill pickles and the chocolate ice cream shell. That's at freshair.npr.org. I'm Terry Gross, and this is FRESH AIR.

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GROSS: This morning, while I was preparing my interview with you, I thought I would ask everybody who works on FRESH AIR if they had any questions they wanted me to ask you about issues they've been having with food preparation. And so I have some for you and I'd love to hear what your answers and I know everyone who works on FRESH AIR would love to hear it too, and I'm sure our listeners will as well, because they're probably having some of the same issues.

Let's start with something really basic. Hamburgers. Lots of people are grilling them for the summer. And both Sam Briger and John Myers of our show want to know, like to make a really good hamburger on a grill, like how thick should you make it? Like what should the size of the patty be? And how do you know when they're done? Because it's so easy for it to be rare in the middle or just to accidentally overcook it.

BISHOP: Well, a couple of things. I think that if you're going to be grilling the hamburger, one of the reasons you want to be grilling it is to get that great crust on the outside, and in order to give the grill enough time to put a crust on it, it's going to have to be a fairly thick patty. You know, if you're starting with a really thin patty, it's going to be overcooked by the time it gets well-browned on the outside, so make it fairly thick.

Another thing that you want to - and fairly thick means probably - I don't know Bridget; I would say three quarters to an inch thick seems about right.

That sounds better.

One of the tricks we found is that a lot of times...

GROSS: Did you thin it toward the edge or keep it that way all the way through?

BISHOP: No. You're going to put a divot center, Terry.

(LAUGHTER)

BISHOP: Because what happens is when the burger is on the grill, the muscle fibers shrink, and what is a flat patty turns into a tennis ball. You get this sort of rounded burger that then is very difficult to put toppings on or put on a bun. And so the way to prevent that is to anticipate the rounding and to put a divot in the top of it, so that means simply going around and pressing about a half inch depression in the sort of center half of the top of the burger, and that will naturally puff up on the grill it will puff up and therefore, be flat. So those are a couple of things.

The other big thing is that, you know, there's a lot of fat in a burger, but they still can stick to the grill. And so preparing the grill properly so that you're able to flip it without losing portions of the burger is really important. And a really simple trick is to take a wad of paper towels that you dip in vegetable oil, hold them with a pair of tongs and use those to grease the grate right before you put the burgers on. It even better with fish - which is always sticking - is to oil those grates. And you don't want to be spraying things because that could be really dangerous. I've seen people spray, you know, use cooking spray outdoors. You do not want to be doing that because you can, you know, get the aerosol to ignite. So you just simply take a wad of paper towels, hold them with a long handled tongs, they're dipped in oil and you just rub them right back and forth where you're going to cook.

GROSS: Oh, that sounds good. And you weren't kidding about the divot.

(LAUGHTER)

BISHOP: I was not kidding about the divot.

GROSS: OK. Speaking of flipping, this is a question from John Sheehan from FRESH AIR. Since, you know, bacteria are such an issue when you're working with raw chicken so, you know, and you don't want to contaminate any surfaces or any cooking utensils with bacteria. So if you're cooking with, you know, a spatula or tongs, what do you do to make sure that you're not contaminating those utensils with bacteria by touching them to the chicken before the chicken is cooked and the bacteria are killed?

BISHOP: This is a great question. I've been asked this before too. So officially, I'm going to tell you that every time your utensils touch the food that you should either clean them or have a few pairs of tongs available. And actually, if people knew how we set up our stations at the Test Kitchen, the test cooks will get a big container and they gather all their tools there. And then they have these kitchen crocs and each of these containers may be has four or five different pairs of tongs. And we use a lot of raw food, lot of raw meat,so contamination is definitely a concern.

For myself, you know, if you're flipping over chicken, I would rinse it under hot water or, you know, quickly wash it off. If I'm out on the grill, the trick that I use is I will stick the tongs through the grill grates quickly over the charcoal so that any - that basically it's incinerating any bacteria that might be on the actual tongs. But Jack, I don't know what to do.

Well, I think the biggest concern is that last time you touched the chicken.

Mm-hmm.

And so, you know, the first 10 times that you're touching the chicken isn't really...

It's still raw.

It still raw or it's still not cooked. But when you're going to take the chicken off of the grill and onto a platter, I want to use a clean pair of tongs and I want to put it on a clean platter. You know, the platter that you used to bring the food out of the grill is not the platter that should be bringing the food back indoors.

(LAUGHTER)

GROSS: Absolutely. Yeah.

BISHOP: Because - yeah. And people don't think about that. And so I will always have a clean platter and a clean pair of tongs for that last transfer of the cooked food onto a clean platter. I'm less concerned about cross-contamination while it's still cooking because, you know, the bacteria is right on the exterior, which is going to get hot and five seconds later...

It's going to be cooked off.

...that bacteria is going to be cooked off.

GROSS: That sounds like a really good advice. Our next for the question comes from Phyllis Myers of FRESH AIR. And she just had I think at a friend's house, a kale salad that was massaged with salt. And it sounded to me like a massage therapist have come in and, kind of, given the treatment to the salad. But I've never heard this before it. I am told that kale salad is really popular right now. So I no kale can be a little bit tough. What kind of tips do you have for a good kale salad?

BISHOP: Believe it or not, we tested the massage theory in the kitchen and it works.

GROSS: Oh.

BISHOP: So your - Phyllis is onto something. You do want to start out with the young, tender leaves. I mean at certain times of the year, especially in the winter, you can get kale that has been out in the field, gone through a couple of frosts and is just big and hearty. And you could massage that for several days and you're not going to want to eat it raw. It's really meant for cooking. So the first thing is to shot properly if you really want to have a kale salad. I actually think the Italian variety of kale; they sometimes call a dinosaur kale, Lacinato kale - see different names. But it's got a kind of mottled dark green surface. It's a little bit bumpy and I just think it has a nice flavor. It makes a better salad. So small leaves, and you are massaging them in the bowl for about five minutes. Now that seems like a lot of work, actually for salad. I'm not sure I'm going to make kale salad and massage it for my guests.

GROSS: How the massage kale? I don't even get it. What are you doing?

BISHOP: You are basically putting the kale in the bowl, and with your hands just rubbing it. And I guess what you're doing - I'm going to sound very sciencey here - is that you're breaking down the cellular structure very gently. You're not trying to mash it or mangle it, but you are making the leaves a little bit more tender. The outside of the leaves can be a little rough, and I think you're basically kind of work using your hands as emery boards.

Exfoliating.

(LAUGHTER)

BISHOP: You're exfoliating with kale, so that it seems a little bit more tender when you go to use it in a salad.

And it definitely preserves its fresh flavor, so you're not cooking the kale in order to soften it. So you definitely get a fresher flavor. But, yeah, if the kale was under some stress and needed a massage, you probably do by the end of it, after massaging the kale.

(LAUGHTER)

GROSS: OK. So this next question about food comes from Danny Miller. And he wants to know like when you're grilling eggplant, should you salt it first to drop the moisture. And he asked this, in part, because he tends to do that and Danny's wife Mary goes with that's just a myth, and Danny goes with his the salt. So you could see there's possibilities, here, for really serious marital conflict over this.

(LAUGHTER)

BISHOP: The eggplant years.

GROSS: Exactly.

BISHOP: I would say well, it depends on two things: the eggplant and how thick you're slicing the eggplant. One of the great things about the grill is that it lets any kind of moisture wick away. So if you have thinly sliced eggplant - just say your regular purple eggplant - you thinly slice it, brush it with a little bit of oil. It's going to go on and off the grill very quickly. It's probably not going to be an issue. However, if you're going to slice it a little bit thicker or into thicker planks, I would still salt it. I would salt it, leave it be in the Test Kitchen is press the eggplant, as well. So after you've salted it, you can put it in between some towels or paper towels, and gently press on it and that compacts its structure a little bit - makes it meatier and it makes it so that it doesn't get mushy on the grill. And then a little bit of olive oil, some herbs over a hot fire, and very quickly on and off.

GROSS: So the answer is? Yes, it is. Yes, salted if it's cut thick.

BISHOP: I would say yes unless he wants to save his marriage.

(LAUGHTER)

BISHOP: And then I would go with his wife's opinion.

GROSS: No. No. But it sounds like this is a, you know, if it's sliced thin and then you don't really need the salt or...

BISHOP: Sliced thin you don't really need to. But I actually like to salt everything before it goes on the grill anyway just for flavor. So, you know, good 10 minutes with salt on it isn't going to hurt anybody. That's the happy medium for them. They can meet in the middle.

GROSS: My guests are Bridget Lancaster and Jack Bishop of the public TV show "America's Test Kitchen." They've contributed to a new "America's Test Kitchen" cookbook called "DIY," "Do It Yourself." More after a break.

This is FRESH AIR.

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GROSS: My guests are Bridget Lancaster and Jack Bishop of the public TV shows "America's Test Kitchen" and "Cook's Country." They've contributed to a new "America's Test Kitchen" "DIY," "Do It Yourself" cookbook. Before talking with them, I asked the FRESH AIR staff for food questions they wanted answers to.

Here's a question from Teresa Madden of our show. She has a lot of zucchini from her CSA, the Community Supported Agriculture, community farm that she buys her produce from. And she doesn't have a grill and she doesn't have good air conditioning or maybe any air conditioning, so she can't grill and she doesn't really want to cook on hot days in the summer. So what can she do with the zucchini that's left over?

BISHOP: I have a revelation if you've never had a rough zucchini salad. Now this is a good use for small to medium zucchini. You know, if you're getting two pounds zucchini that are kind of watery and full of seeds, I'm not sure I would use this recipe for it. But if you've got six or eight ounce, you know, what I would call medium or small zucchini, sliced them really thin. You know, if you have a mandolin, you can get an inexpensive plastic mandolin at any house ware store, and you just basically slicing it as thin as you can. If you've got a great sharp knife, you can use a knife as well. But at least, you know, and eighth of an inch better at a 16th of an inch thick. I like to slice it on the bias so I can get sort of longer pieces of the zucchini. You can do it with the Golden zucchini, you can do it with summer squash. I put them on a platter. I will then shave Parmesan cheese, throw some fresh herbs - basil, mints, chives, drizzle it with the best extra virgin olive oil you have, salt and pepper, and it is the perfect, you know, first course raw zucchini salad that is a great way to start any summer meal.

GROSS: Is there anything inside it besides the zucchini?

BISHOP: It is zucchini. I like to put the Parmesan and the herbs, but you can really be simple - a zucchini, salt, pepper and olive oil.

GROSS: But I mean no other vegetables or no grains or anything, just the zucchini?

BISHOP: No. Just the zucchini. Well, you asked for ways to use a raw zucchini.

GROSS: Yeah. No. Definitely.

(LAUGHTER)

GROSS: This is not, you know, one of those recipes where you use one zucchini. You're going to need a couple of pounds of zucchini if you're making this salad for let's say six people, you're probably going to want, you know, two pounds of zucchini. That's why you - the mandolin could go very quickly. You know, unless you've got good knife skills, it can be a lot of slicing, and it really depends on getting paper thin slices of the zucchini that are just really great raw. And it doesn't heat up the kitchen. You really sort of get a different textual experience of the zucchini. You know, it's not that soft kind of mushy zucchini that often happens when you saute it. And it's just a great canvas for, you know, salt, pepper, olive oil, Parmesan and herbs.

Well, poof, you've solved the extra zucchini problem.

(LAUGHTER)

GROSS: OK. From Roberta Shorrock of our show, the question is, so how long can you keep out the potato salad - like if you're at a picnic or something?

BISHOP: Potato salad, I believe the potato salad, the enemy in there is the potato - not the actual mayonnaise.

GROSS: Really? I thought it was the mayonnaise.

BISHOP: Well, store-bought mayonnaise - this is very different from homemade mayonnaise. But store-bought mayonnaise has so many preservatives in it. Now I'm not saying to put it in the back, you know, window of your car and drive around and leave it, but potato salad, what happens, I'm not exact - Jack, I can't actually remember what happens with the potato.

Bridget is right. The potato is the problem - that there is naturally occurring bacteria. And the rules are really pretty simple. It's, you know, two hours at a picnic unless it's really hot and really sunny, and really hot means above 90 degrees and then you've got an hour that it should be out of refrigeration. Otherwise, potato salad needs to be, you know, at 34, 35 degrees in the refrigerator. The source of the problem begins with the potatoes and then the mayonnaise is simply the mechanism that allows the nasty bugs to grow. And so the mayonnaise is a little guilty but really guilt...

LANCASTER: It's the carrier.

BISHOP: Yes. So really, you know, on a hot day an hour is really all anything really should stay out on the picnic table that's, you know, a raw food like that or cooked foods. That it can really be a breeding ground for trouble.

GROSS: OK. Another question from Roberta. She's buying fresh peaches and finds if she keeps them close together that they seem to ripen faster - too fast. How can she slow it down?

BISHOP: Well, most fruits have something called ethylene. Bananas are famous for having a tremendous amount of ethylene. So you can throw, you know, a banana in the bag with something to help ripen it. But all fruits have some amount of them. And so obviously the closer they are together they're sort of combining that effect. And the ethylene is a naturally occurring gas they give off that helps ripen peaches, tomatoes, bananas.

So separating them on the counter is a good idea. Keeping them out of the light - you know, a lot of people want to put things on the window sill, think they're displaying, you know, the things they picked up at the farmer's market. But what they're beginning to do is actually cook it.

GROSS: Mm-hmm.

BISHOP: Because it's sitting in the sunlight. And so not near the stove, not near the window. You know, put them on the counter in the cool corner somewhere away from sunlight and they will stay fresher longer. I do like to keep them out of the fridge until they're fully ripe because their flesh will change and if you put them in the refrigerator before that they are really ready to be eaten, they get kind of mealy.

LANCASTER: They have that Styrofoam texture. Yeah.

BISHOP: Yeah. And so they - once they're ripe you can put them in the refrigerator to help prevent them from, you know, getting sort of rotten in the last two days in the refrigerator. But keep them on the counter until they're soft enough to eat.

LANCASTER: But I think that's the problem with peaches or a lot of different fruit, is that people buy them, they put them in the paper sack and they leave them in the paper sack. So they are all trapped together giving off the ethylene gas to each other. So they definitely over ripen very quickly.

GROSS: Do fruits give off ethylene gas once they're in the refrigerator?

LANCASTER: Small amounts. But it definitely slows down. Because it really is about the ripening process. They're giving off that gas during the ripening process. So just by slowing it down in the fridge, you're not actually stopping it completely.

GROSS: So this comes from Lauren Krenzel of our show. What are the best fishes to grill?

BISHOP: When you're choosing a fish to grill, two things you want to think about. Is it sturdy? You know, if it's one of those flaky fish - I see people trying to grill cod or, you know...

LANCASTER: Flounder.

BISHOP: Flounder. That's just - you're headed for trouble. So you want a meaty fish that stays together when it's cooked. And if it's a fish that flakes apart very easily, it really belongs indoors, you know, in a skillet, in the oven, something like that. The second thing is thicker is better. That really thin pieces of fish are hard to grill, in part because you can leave them on the grill longer before you have to turn them without overcooking them.

And the longer you can leave it on the grill the more of a crust you're going to get on a fish and the less likely that it's going to fall apart when you go to flip it or take it off the grill. And so salmon is great. Tuna.

LANCASTER: Tuna is great. It's made for the grill.

BISHOP: Yeah. Swordfish. You know, they're all - halibut.

LANCASTER: Halibut steaks. Yeah.

BISHOP: They're all meaty, they're all about an inch thick which helps. Most of those that I just named have a fair amount of fat in them. Not the tuna, but especially the salmon. Which helps, you know, prevent sticking and works nicely on the grill.

GROSS: This question comes from Heidi Saman, and it's actually from her husband, Joe(ph), who does a lot of cooking. And he's been heading in a more vegan direction and wants to know your suggestions for how to grill and marinate tofu.

BISHOP: It's a sponge. You know, tofu is a lot like eggplant. And that's a good thing in the sense that it is a blank canvas that will soak up whatever flavors you want to give it. Unlike meat, where marinating can sometimes take a fair amount of time, tofu, 20 minutes is going to be enough. And so basically marinate it as long as it takes for you to get the grill going.

I think the best way to do it - don't bother trying to cut it into cubes or skewer it - is simply to take extra firm tofu - don't try to do the soft tofu - cut it crosswise into eight slabs. So if you have that package, it's either 14 or 16 ounces, you're basically cutting it into little rectangular cutlets that are each maybe three-quarters of an inch thick. And you've taken, you know, that one block, cut it into eight pieces.

Put them in a baking dish. Any marinade that you like. Soy always makes sense with tofu. The salt makes most things taste better. Add something, a little bit of sweet, maybe a little hoisin or oyster sauce. Add a little bit of oil, some vegetable oil so that it won't stick. You can add some spices, five spice powder, chipotle chilies.

I mean, you want to use the strong flavors with the tofu because the reverse of it being a blank canvas is it can be very boring. And so if you don't use strong flavors in the marinade it will be a little bit boring. This is a good time to use the oiled paper towel to oil down that grill great because the tofu can stick. So you take the wad of paper towels with the oil and rub - hold them with the tongs and rub that back and forth.

Grill them just until they're lightly charred on each side and, you know, it's a really great way to make a vegan summer grill entrée.

GROSS: Do you eat grilled tofu yourself?

BISHOP: I do. I love tofu. We probably have tofu once a week at my house. I either grill it or I pan sear it. And I would say most of the year I'm pan searing it, but then adding a lot of flavors to it for just that reason. My kids love it with sesame and scallions and ginger and soy sauce. And, you know, you can serve it with rice and vegetables and it's a great meal.

GROSS: This might've been the first time I've heard anybody say my kids love tofu.

(LAUGHTER)

BISHOP: My kids ask for tofu.

GROSS: Really?

BISHOP: And they're not even really particularly adventurous.

GROSS: It's a tribute to your cooking.

(LAUGHTER)

BISHOP: You know, it's simple. And the texture is great. You know, it's really important after you've sliced it when you're going to be pan searing it is to blot it dry. It's less important on the grill because the grill will allow excess moisture to drop down, you know, onto the coals or onto the flames. But a lot of people don't dry the tofu enough and, you know, it's going to be a little flabby.

And so once I've sliced it I always put it between paper towels for 10 or 20 minutes, press on it very lightly with my hands, so that it's nice and dry, and that allows it to then soak up more of those flavors, whatever you're cooking it with.

GROSS: My guests are Jack Bishop and Bridget Lancaster of the Public TV show "America's Test Kitchen." They've contributed to the new "America's Test Kitchen DIY Cookbook." More after a break. This is FRESH AIR.

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GROSS: If you're just joining us, my guests are Bridget Lancaster and Jack Bishop of the Public Television show "America's Test Kitchen" and "Cooks Country." They've also contributed to the new "America's Test Kitchen Cookbook," DIY cookbook, the do-it-yourself cookbook. And I'm now asking them questions that come from the FRESH AIR staff about issues they're having with cooking.

Here's a question from Molly Seavy-Nesper of our show. What do you think about grilling fruit? And if you like that idea which fruits and how to do it?

LANCASTER: I wouldn't say that I am in the I-like-grilling-all-fruit camp. I love fresh fruit uncooked as much as possible. However, grilled pineapple is one of my very favorite things. It has so much natural sugar in it. Or there's other fruits. Mango. Some people like to do kabobs of berries. I'm not too into that. But you just brush it with a little bit of an oil that's very neutral in flavor.

So something a little bit like a vegetable oil, just very lightly. Or you can even spray it with vegetable oil spray and quickly over the fire. You're just really searing it. You're not trying to cook it all the way through because it's raw fruit. But to me pineapple and the grill is a magic combination because it caramelizes the sugars. It concentrates that pineapple flavor and it's absolutely delicious.

GROSS: Jack, any thoughts?

BISHOP: The two fruits that I grill are lemons and peaches. And the lemons, I will actually cut them into, with the skin still on, kind of one-inch pieces and put them on kabobs. And, you know, sort of alternate that with chicken. I think it's really particularly good with chicken and the vegetables. And grilled lemons, they get kind of sweet and charred. They add some juiciness, some flavor.

And so if you - an interesting way to grill the fruit is to cut it kind of the way you would cut eggplant or zucchini but put some lemons on. Now, you don't want to go overboard. You know, two lemon pieces, maybe three, per skewer is fine. I'm not sure you want a skewer that has 10 pieces of lemon on it. The other one is peaches and I will have them...

GROSS: Wait. Let me just stop you. Do you actually eat the lemon or is that just for flavoring?

BISHOP: No, I eat the lemon.

GROSS: Mm-hmm. OK.

BISHOP: I eat the skin and all. I mean...

GROSS: Wow. OK.

BISHOP: ..you will wash the - you want to wash it well. So, you know, if there's any wax on it, to get rid of that. So wash it under some hot water and scrub it with a little vegetable brush so it's nice and clean. And obviously the lemons that don't have a stamp on them. You know, it's not very attractive if it has a label on it that's been stamped. So if you're going to be eating it, check that at the supermarket.

(LAUGHTER)

BISHOP: And try to get one of the organic lemons that hasn't been stamped with a brand name on it. And certainly if it's got a peel-off sticker, make sure to peal off the sticker. But, yeah, it's a really interesting way to eat lemon. That's why I said you're not going to want to eat a lot of those pieces, but you put a couple of those on - it could be grilled with fish, swordfish in particular. But I do it a lot with chicken.

And no one's ever had it - when they're at my house they're like, really, you eat the lemon? I'm like, try it. And everyone's convinced once they eat the lemon.

LANCASTER: It definitely tempers the acidity too.

GROSS: Yeah. OK.

LANCASTER: That little bit of cooking.

GROSS: And what about the peaches, the grilled peaches?

BISHOP: The peaches, halve and pit them. Brush them lightly with oil. And I think grilled peaches and pork is a natural combination. The only trick is you want to get ripe but still firm peaches. You know, if it's a peach that's so ripe that it's going to run down your chin and neck as you're eating it, you're going to have a little bit of trouble probably with it on the grill.

You don't want use the rock hard awful tasting peaches, but you want to catch it right before it's soft. But when it's ripe cut it in half, brush it with oil, and it's just a great accompaniment to pork chops, pork roast, on the grill.

GROSS: Well, I want to thank you both so much for your suggestions. It's always a pleasure to talk with you. Thank you for coming back to FRESH AIR.

LANCASTER: Thank you.

BISHOP: Thank you.

GROSS: Bridget Lancaster and Jack Bishop are with the Public TV show "America's Test Kitchen" and contributed to the new "America's Test Kitchen DIY Do-It-Yourself Cookbook." On our website you'll find three of the recipes they talked about earlier in the show for oven dried tomatoes, sour dill pickles, and a chocolate ice cream shell. That's at freshair.npr.org. Transcript provided by NPR, Copyright NPR.