In a large bowl, whisk together the flour, sugar, and salt. Add the chilled shortening pieces.

Use the tines of a fork (or a pastry cutter) to cut the shortening into the flour. Crucial: Stop when the mixture looks like coarse crumbs with some pieces the size of small peas. Those "peas" of fat are what create the flaky layers.

In a separate small bowl, whisk the egg and ice water together. Pour this into the flour mixture.

Stir gently with a fork until the dough just starts to come together. Use your hands to press it into a disk, but do not knead it. Over-handling develops gluten, which makes the crust tough.

Wrap the disk in plastic wrap and refrigerate for at least 1 hour. This allows the flour to fully hydrate and the fat to firm back up.

On a lightly floured surface, roll the dough from the center outward into a circle about 2 inches wider than your pie pan.

Once the dough is in the pan, use a fork to prick the bottom several times (this is called "docking"). This prevents the crust from puffing up or bubbling during the pre-bake.

Cover the fluted edges with aluminum foil. Bake at 350°F for 30–40 minutes.

Let the crust cool completely to room temperature before adding your filling. This prevents the bottom from becoming soggy.