The Food Lab's Top 9 Tips For Perfect Apple Pie

Here are the most essential tips and techniques that will guarantee a perfect pie for your Thanksgiving table.

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Photographs: J. Kenji Lopez-Alt

The perfect pie is equal parts science and art, and there are few things more intimidating in the American culinary repertoire than pie crust. How many of you have slaved away at a crust only to have it crumble upon rolling? How many of you have pulled a beautiful pie out of the oven only to realize upon slicing into it that the perfectly golden brown crust is leathery or tough? Or that your apple pie filling has turned mushy in the oven?

Well we've got some solutions for you. In the past, we've already gone into great detail about how to make perfect pie crust that's bakes up flaky and tender, and is a snap to roll out. We've also discussed the best apples to use, as well as how to cook them. Thousands of words of detail. Yeesh.

Consider this the tl/dr version. The most essential tips and techniques that will guarantee a perfect pie for your Thanksgiving table.

Perfect Pie Tip #1: Keep It Cold

For the flakiest, most tender crust, it's essential that you keep all of your ingredients and equipment cold as you work. See, flaky layers in the crust are formed when chunks of butter (or pockets of butter-flour paste) are pressed out and flattened in between layers of gluten (the protein network that forms when flour and water mix). These alternating layers are absolutely key.

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If your butter (which I prefer over lard or shortening—see tip #3) gets too warm, it'll end up mixing with the gluten layers, and rather than forming distinct flakes, you'll end up with a single, greasy, shortbread-like crust.

To prevent this, make sure that your butter stays in the fridge until you are ready to use it. Keep your water (and vodka, if you care to use it, see tip #4) ice cold. Chill your flour if your kitchen is particularly warm, and if necessary, place everything in the freezer in between steps to chill them down.

Perfect Pie Tip #2: Use All Butter

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Many traditional pie crust recipes call for a mixture of butter and shortening, or for leaf lard—rendered fat that comes from around a pig's kidney. Both shortening and leaf lard are more malleable at refrigerator temperatures than butter, making them easier to work with and creating a pie dough that can roll out easily without the need to add too much water (which can make for a tough, leathery crust). The downside is that both shortening and leaf lard are relatively flavorless.*

An all-butter crust has much better flavor than the alternatives, but because butter is so hard until it melts, it can be more difficult to work with. The solution to that problem is to incorporate the butter in a unique way...

*Commercial lard, on the other hand, is rendered fat from all over the pig and can have a somewhat gamy, off-putting flavor. I don't recommend it either.

Perfect Pie Tip #3: Form A Butter-Flour Paste, And Add Flour In Batches

This is where our easy pie dough diverges wildly from most pie crust recipes out there. Most recipes will have you cut your fat into your flour until "it resembles coarse meal" or until "pea-sized chunks remain." The problem is, not only is this a fairly inaccurate standard (ask 10 people to do it and you'll get 10 different results—heck, ask 1 person to do it 10 times, and you'll probably get 10 different results), it also makes for a crust that's crumbly and hard to roll out.

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But there's another, better way to get results that are even more flaky and tender. Start with 2/3rds of the flour and the fat in the bowl of a food processor and process until it forms a nearly dough-like consistency, like a pâte sucrée. Then, add the remaining flour and pulse just to distribute it evenly. What you end up with is the perfect amount of free flour to form gluten when you add water, and the perfect amount of fat/flour paste to keep those gluten layers separated. And because the fat/flour paste is far more malleable than plan butter, your dough will also be incredibly easy to roll out.

Perfect Pie Tip #4: Use Vodka (or Don't)

Back in 2007, I developed a pie crust recipe for Cook's Illustrated using vodka to replace part of the water. The idea was that since gluten doesn't form in ethanol and vodka is 40% ethanol, you can actually add more liquid to your pie crust if you hydrate it with vodka than if you do with pure water, which makes it easier to roll out. The ethanol all evaporates as it bakes, leaving a perfect crust behind.

While many people now swear by this recipe (and you can find the full recipe here), I've stopped using it at home altogether. For one thing, I don't often have vodka at home and my pie crust days are usually spur-of-the-moment. For another, with the method outlined in tip #3 above, I just don't see the necessity—the dough ends up perfectly rollable with or without the addition of extra liquid.

Perfect Pie Tip #5: Use A Spatula To Incorporate Water

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Your processed flour and butter are sitting there in the bowl of your food processor and you're tempted to save yourself a bit of cleanup by just adding the water directly in there, right? Don't do it! Sure, it'll work out ok, but you won't form nearly the same level of flakiness as you do if you incorporate with a spatula. Here's what a crust made 100 percent in the food processor looks like:

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Compare that to the crust I made above with the spatula:

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See the difference? By using the spatula to fold the water into the crust, you give flaky layer formation a head-start even before you pull out the rolling pin.

Perfect Pie Tip #6: Choose Tart Apples

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You may think that picking the right apple for a pie is all about flavor, but there's another equally important element: pectin. Pectin is the biological glue that holds together plant cells, giving fruits and vegetables their shape and structure. When apples are cooked, this pectin breaks down, and the apples turn mushy.

However, there are ways to control this pectin breakdown, helping you to ensure that your apple slices are tender, but still hold their shape in the pie. The easiest first step is to pick the right apple. Pectin breakdown is inhibited by low pH levels (that is, it breaks down less when the environment is acidic). Thus the tarter the apple, the more likely it is to hold its shape upon baking.

Interestingly enough, tartness also prevents oxidation reactions that can turn apple slices brown. So by examining which apple slices turn the brownest after slicing, we get a pretty good gauge of their acid content.

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As you can see, Red Delicious, McIntosh, and Braeburn brown the most and will tend to break down completely upon baking. Meanwhile, Granny Smith, Royal Gala, Empire, Cortland, and Golden Delicious will all fare far better. I like to use Golden Delicious because of their perfume-like aroma, but any tart apple will work.

Perfect Pie Tip #7: Go Easy on the Seasoning

Too often apple pies taste of nothing but cinnamon and nutmeg, not like apple. I like my apple pies to taste first and foremost apple-y, which is why I only use a small amount (1/4 teaspoon per 4 pounds) of spices.

Perfect Pie Tip #8: Par-Cook Your Apples

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It may seem counterintuitive, but par-cooking your apples either by stirring them in a pan on the stovetop, by heating them in the microwave, by cooking them in a sous-vide setup, or by pouring boiling water over them and letting them sit for 10 minutes will make for apples that hold their shape better when you bake them. How is this possible?

Remember that pectin holding cells together? Well, heating it in a controlled manner—letting it spend a few minutes in the temperature zone between 140 and 160°F will increase the activity of an enzyme that converts pectin into a more heat stable form. Very much like curing the cement mortar in between the bricks in a wall and allowing them it fully harden. Once your apple slices have been pre-treated in such a manner, subsequent baking will tenderize them, but still allow them to maintain their shape.

All you've got to do is heat up a pre-determined amount of water (I use 3 quarts per 4 pounds of apples) on the stovetop to a boil and pour it directly over your room temperature apples in a bowl. If everything is measured right, you end up with apples sitting right at around 160°F. Cover the bowl, let it rest 10 minutes, drain the apple slices, and you're good to go. If you're in the mood for hot cider and a bit of extra flavor in your pie, you can do the exact same thing using cider instead of water.

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After ten minutes in the bowl, your slices will have softened ever so slightly, but still retain most of their form. After this point, even if you bake them into a pie, they still pretty much retain their basic shape and a bit of pleasant al dente firmness.

As an added bonus, par-cooking your apples will get rid of the air pocket that can occur between the top of the apples and the crust when you add your apples raw.

Perfect Pie Tip #9: Let It Rest!

Hot apple pie fresh out of the oven might sound appealing, but letting it rest for a couple of hours will give you better results in the end. For one thing, most recipes are designed for optimum texture at room temperature. Slice that pie while it's too hot, and it'll be runny and wet instead of perfectly glazed and juicy. Pie crust also fares better at room temperature, where it'll have a flakier, crisper texture.

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