1. Pulse flour and salt in a food processor 3 or 4 times or until combined. Add butter, and pulse 5 or 6 times or until mixture resembles coarse meal. With processor running, gradually add 1/4 cup ice-cold water, and process just until dough forms a ball and pulls away from sides of bowl, adding up to 1/4 cup more ice-cold water if needed.
2. Gently form dough into a flat disk; wrap in plastic wrap, and chill 1 hour to 2 days.
3. Preheat oven to 400°. Roll dough into a 12-inch circle (about 1/8 inch thick) on a lightly floured surface. Fit into a lightly greased 9-inch round tart pan with removable bottom, pressing dough on bottom and up sides into fluted edges.
4. Line dough with parchment paper, and fill with pie weights or dried beans.
5. Bake at 400° for 20 minutes. Remove weights and parchment paper, and bake 15 to 20 more minutes or until bottom is golden. Transfer to a wire rack. Cool completely (about 30 minutes).