What's the secret to a flaky piecrust?

Opinions differ on this one, but we’d put our money on lard. Some recipes call for part lard, part butter. Others use whole wheat flour and vegetable shortening or oil. Some bakers swear by Crisco. But lard has one surefire advantage over other ingredients: It mixes unevenly with flour. Scientifically speaking, it has a rough crystalline structure that results in a flakiness that other ingredients can’t match. (Butter comes close, however, and some prefer its taste.) We won’t deny the health costs of lard. It’s rendered hog fat, after all, made by heating and then chilling the fat around the back and abdomen of the creature. It won’t do your cholesterol count any good, but it does tend to be inexpensive and widely available. To make a basic double crust for an 8- or 9-inch pie, use this recipe: Place 2 cups flour and 1/2 teaspoon salt in a bowl and whisk to mix. Cut in 2/3 cup lard with two knives or a pastry blender until the pieces are no bigger than peas. Add ice water, a tablespoon at a time (up to 6 tablespoons), until the dough just holds together. Form the dough into two balls, one slightly larger for the bottom crust. Flatten the balls to about an inch thick, wrap in plastic or waxed paper, and chill for at least an hour. Roll out on a floured board without stretching the dough. Line your pie plate with the bottom crust, fill as desired, and cover with the top crust.