Place the butter in the refrigerator (or freezer for 10 minutes) so it is very cold. Fill a small cup with cold water and a few ice cubes; let it sit while you prepare the dry ingredients. If using vinegar or lemon juice, add it to this water.

In a medium mixing bowl, whisk together the flour, salt, and sugar (if using) until evenly combined and slightly aerated.

Add the cold, cubed butter to the flour mixture. Using a pastry cutter, two knives, or your fingertips, cut or rub the butter into the flour until you have a mixture with some pea-sized pieces and some smaller, coarse-crumb pieces. You should still see visible bits of butter—do not work it until the butter disappears.

Sprinkle 3 tablespoons of ice-cold water over the flour-butter mixture. Using a fork, gently toss and fold the mixture to moisten it without mashing. Squeeze a small handful of dough: if it holds together and still looks shaggy, it’s ready. If it crumbles apart and looks dry, add up to 2 more tablespoons of ice water, a teaspoon at a time, just until the dough barely comes together. It should not feel wet or like cookie dough.

Turn the shaggy mixture out onto a clean countertop or sheet of parchment. Using your hands, gently press and gather it into a ball, incorporating any dry bits, but avoid kneading. Flatten into a disc about 1 inch thick. Wrap the disc tightly in plastic wrap or reusable wrap and refrigerate for at least 1 hour and up to 3 days to hydrate the flour, firm the butter, and relax the gluten.

Lightly flour your work surface and rolling pin. Place the chilled dough disc in the center. If it is very firm, let it rest at room temperature for 3–5 minutes. Roll from the center outward, turning the dough a quarter turn every few rolls and lightly dusting with flour as needed to prevent sticking. Roll into a 12-inch circle about 1/8 inch thick for a standard 9-inch pie dish. Patch and gently press together any cracks at the edges.

Carefully roll the dough loosely around the rolling pin or fold it into quarters, then transfer and unroll or unfold it into a 9-inch pie dish. Ease the dough into the bottom and up the sides without stretching. Trim so there is about a 1-inch overhang, fold the overhang under itself along the rim to create a thicker edge, and crimp with your fingers or press with a fork.

For pies that require a pre-baked crust (such as cream pies or some custard pies), chill the shaped crust in the refrigerator for 20–30 minutes. Heat the oven to 375°F (190°C). Line the chilled crust with parchment paper and fill with pie weights or dried beans. Bake for 15–20 minutes, then carefully remove the parchment and weights and continue baking until the bottom looks set and the crust is golden. Cool before filling.

For pies such as apple pie or chicken pot pie, add your prepared filling to the unbaked crust. If using a top crust, place it over the filling, seal and crimp edges, and cut vents as needed. Chill the assembled pie for about 15 minutes before baking, then bake according to your filling recipe, usually between 375°F and 425°F, until the crust is deep golden and the bottom is set.