Pie crust: less water
When flour meets water, its proteins link into gluten, which bakes up stretchy and tough. Great for bread, bad for pie. Use just enough water to hold the dough together. It should look shaggy and a bit crumbly.
Cold fat and a rest
Cold butter stays in pieces through mixing. In the oven they melt and their water turns to steam, leaving flaky gaps. A rest in the fridge also relaxes the gluten, so the crust rolls out easier and shrinks less.
Test yourself
Questions from the interactive lesson, with the answer and the why.
Why does pie dough use as little water as it can?
More water builds more gluten, and gluten toughens. Gluten forms when flour proteins meet water, and too much makes a chewy crust.
True or false: Cold chunks of fat in pie dough melt in the oven and leave small gaps, which gives a flaky crust.
True. Solid fat pieces melt in the oven, and their water turns to steam, leaving gaps.
What went wrong? You knead pie dough until it's smooth, like bread dough. The baked crust is tough and shrinks from the sides.
Working the dough built gluten that pulled it tight. Kneading links gluten, which turns the crust tough and makes it spring back.
Fill the blank: Resting the dough lets the gluten ___, so the crust shrinks less in the oven.
Resting the dough lets the gluten relax, so the crust shrinks less in the oven. Relaxed gluten stops snapping back, so the crust holds its size.
Your dough cracks and crumbles when you roll it. What's the best fix?
Sprinkle on a little cold water and press together. A touch more water binds the dry flour with only a small gain in gluten.