In a large bowl, combine all-purpose flour, salt, and sugar. Whisk to evenly distribute. Add shortening and use a pastry cutter or fingers to mix until the texture resembles coarse crumbs.

Beat the egg in a small bowl. Add the egg and cold water to the flour mixture. Gently combine using a spoon or hands until a dough forms. Avoid overworking the dough.

Divide the dough into 4 equal portions. Wrap each portion in plastic wrap and refrigerate for at least 30 minutes. This step ensures a flaky crust.

Lightly flour your work surface and rolling pin. Roll out one portion of dough to about 1/8 to 1/4 inch thick, ensuring it fits your pie pan. Transfer the dough to the pan and press gently to shape. Trim and crimp the edges.

For pre-baking, poke holes in the bottom with a fork to prevent bubbling and bake according to your recipe. For filled pies, follow the specific baking instructions in your pie recipe.