In the bowl of a food processor, pulse together flour and shortening until mixture looks like course crumbs. In a measuring cup mix your egg, water, vinegar, and salt together.
Add liquid mixture to the flour mixture until a dough forms in your processor. Divide into 4 equal dough balls. Place each dough ball in plastic wrap and refrigerate overnight or freeze them.
Remove from refrigerator to roll or let frozen dough thaw 30 minutes or until soft. Roll out and fit into pie plate. Bake empty at 400 10-12 minutes or until golden or put filling of your choice. (as your recipe directs)