Put the cold butter in the freezer for about 30 minutes, or until firm enough to grate cleanly. It should make distinct shreds rather than smear against the grater. Have ice water ready and measure the water without adding ice cubes to the dough.
1 cup unsalted butter, 6–12 tablespoons ice water
Stir the flour and salt together. Grate the firm butter through the large holes of a box grater into the flour, pausing to toss the shreds with flour. Keep the shreds separate and cold; do not rub the mixture into a smooth paste.
2 1/2 cups all-purpose flour, 1 teaspoon table salt, 1 cup unsalted butter
Drizzle 6 tablespoons of ice water over the mixture and toss gently with a fork. Squeeze a small handful. If it falls apart or contains dry flour pockets, add another tablespoon of water and toss again. Repeat only until a squeezed portion holds together without crumbling. The full 12 tablespoons may not be needed. Stop before the dough becomes wet or sticky.
6–12 tablespoons ice water
Gather the dough with gentle pressure, without kneading. Divide it equally and flatten into two disks. Wrap each disk tightly and refrigerate for at least 2 hours. Visible small butter flecks are expected.
Work with one disk while the other stays chilled. If the disk is too hard to roll without cracking, let it stand for 10–15 minutes, just until workable. On a lightly floured surface, roll from the center outward, turning the dough regularly, to a circle about 12 inches across and about 1/8 inch thick. If it becomes soft or greasy, refrigerate it before continuing.
2 1/2 cups all-purpose flour
Lift the dough into a standard 9-inch pie plate. Ease it into the base and corners without pulling or stretching. Leave about 1 inch of overhang. For a single crust, fold the overhang under and crimp; for a double-crust pie, leave it uncrimped until the filling and top crust are added. Refrigerate the shaped dough for at least 30 minutes. Prepare the second disk the same way if making two single-crust pies.
The dough is now ready for your pie recipe and must be baked before eating. For a pie baked with its filling, follow that recipe's temperature and time. For a filling that needs a partially or fully baked shell, use the blind-baking guidance in the notes. Keep the second disk wrapped and refrigerated if you are not using it immediately.