Add flour, butter, and salt to a food processor. Pulse until the mixture resembles coarse breadcrumbs. With the motor running, gradually pour ice water through the feed tube, just until the dough starts to come together. If it still looks too dry, add more water, ½ tablespoon at a time, but be careful not to overdo it - the dough shouldn’t be sticky.
Pulse until it begins to form a rough ball. Flatten into a disc and wrap tightly in plastic wrap. Refrigerate for at least 30 minutes. This can be made a day in advance.
Preheat oven to 400°F (200°C). Place the dough on a floured surface and sprinkle a little flour over the top. Roll out to a circle about 1/8 inch thick and 11 inches in diameter.
Transfer to a lightly greased 9-inch quiche pan and gently press into the bottom and sides of it. Run the rolling pin over the top to remove any overhanging dough. Using a fork, gently poke holes across the bottom of the pastry, making sure not to pierce all the way through.
Line the inside of the crust with parchment paper or aluminum foil and fill with pie weights, rice, or dried beans. Bake for 15 minutes. Remove the parchment paper and weights, then bake for an additional 10 minutes until the crust is lightly browned.
