Step 1 In a large bowl, whisk together the flour, sugar and salt. Using a pastry cutter or two knives, cut the butter into the flour mixture until flour is coated but some coarse, visible pieces of butter remain.
Step 2 Break the egg into a small bowl and whisk to break apart. Add it to the flour/butter mixture, drizzling in only enough to bind the mixture and make it cohesive; gently mix until the dough comes together when gently pressed. Turn the dough out onto a lightly floured work surface and roll out into a 12-inch circle. (If the dough warms too much and is too hard to handle at any point, refrigerate it until it firms up.) Place in a 9-inch pie pan, crimp the edges as desired, then refrigerate for 20 minutes. Meanwhile, heat the oven to 375 degrees.
Step 3Parbake the crust: Line the bottom of the crust with foil or parchment paper and weigh down with pie weights, rice or dried beans. Place the crust in the oven and bake for 15 minutes. Remove the weights and bake until the crust is lightly colored with no damp spots, about 5 minutes. Remove from heat. If not filling right away, the crust can be stored at room temperature for up to a day before baking.