Pot Pie Crust

1 2/3 cups (8 1/4 ounces) unbleached all-purpose flour, plus additional for work surface 3/4 teaspoon table salt10 tablespoons (1 1/4 sticks) cold, unsalted butter, cut into 1/2-inch pieces and frozen for 10 minutes2 tablespoons sour cream4-6 tablespoons ice waterProcess flour and salt together in food processor until combined, about 3 seconds. Add butter and pulse until size of large peas, about six to eight 1-second pulses.Mix sour cream and 4 tablespoons ice water in small bowl until combined. Add half of sour cream mixture to flour mixture; pulse for three 1-second pulses. Repeat with remaining sour cream mixture. Pinch dough with fingers; if dough is floury, dry, and does not hold together, add 1 to 2 additional tablespoons water and process until dough forms large clumps and no dry flour remains, three to five 1-second pulses. Turn dough onto work surface. Shape into ball and flatten to 5-inch disk; wrap in plastic and refrigerate until firm but not hard, 1 to 2 hours. (Dough can be refrigerated overnight.) To roll out the dough: (If dough has been chilled longer than 2 hours, let stand at room temperature for 15 minutes before rolling.) Dust 16-by-12-inch sheet of parchment paper liberally with flour; roll, flute, and cut vent holes according to illustrations above. Transfer parchment and dough to baking sheet; chill in freezer until ready to use, at least 30 minutes (or refrigerate for 1 hour). Cook's Illustrated, February 2006