Step 1

In a large bowl, mix together the flour and salt. Add the shortening and butter. With a pastry cutter or your fingers, work the shortening and butter into the flour until the mixture resembles coarse crumbs, 3 to 4 minutes.

Step 2

In a small bowl, beat the egg with a fork and pour it into the flour mixture. Add the ice water and vinegar. Stir gently until just combined and the dough holds together when pinched. If the dough does not hold together when pinched, add more water, 1 teaspoon at a time.

Step 3

Divide the dough into 2 equal pieces. Form them into balls, then place each ball in a 1-gallon zip-top plastic bag (do not seal). Using a rolling pin, slightly flatten each ball of dough into a disk (about ½ inch thick) to make rolling easier later. Seal the bags and place them in the freezer until firm, about 30 minutes.

Step 4

When you are ready to use the dough to make a crust, remove from the freezer. On a generously floured surface, roll out the dough with a rolling pin, starting at the center and working your way out. Be gentle and patient; it'll take a little time to get the dough completely rolled out. If the dough sticks to the countertop, use a metal spatula or bench scraper to gently loosen and flip it, adding more flour to the surface and dough as needed. Continue rolling until the dough is approximately 2 inches larger than your pie plate.

Step 5

To transfer the dough, loosen it again with a spatula and lift the pie crust into a 9-inch pie plate (or you can roll the pastry over the rolling pin, lift it onto the pie plate, and unroll it). Lift the edges of the dough gently and allow the dough to settle naturally into the plate, fitting snugly along the bottom and sides without pressing or stretching (to avoid shrinking during baking). Trim any excess dough, leaving an overhang of about 1 inch. Go around the pie plate, pinching and tucking the dough under itself to create a clean edge.

Step 6

If you are making a single-crust pie, crimp or flute the edges as desired, using a fork or your fingers. The crust is now ready to be par-baked or filled, as your recipe specifies. If you are making a double-crust pie, roll out the remaining dough and use it to top your filling.