2 cups all-purpose flour
3/4 teaspoon salt
1 cup Crisco shortening
2 tablespoons ice cold water (put some water in a glass with a few ice cubes, then measure the chilled water from the glass)
1 tbsp cold white vinegar
Blend flour and salt in chilled medium-sized metal bowl.
Cut shortening into flour mixture using a pastry blender until mixture resembles coarse crumbs with some small pea-sized pieces remaining.
Combine egg, water, and vinegar and beat until light. Pour evenly over flour mixture. Stir with fork until mixture is moistened.
Test dough for proper moistness by squeezing a marble-sized ball of dough in your hand. If it holds together firmly, do not add any additional water. If the dough crumbles, add more water by the teaspoonful, until dough is moist enough to form a smooth ball when pressed together.
Divide dough in two, one ball slightly larger than the other. Wrap dough in plastic wrap and chill for 30 minutes or up to 2 days.
Flatten balls into 1/2-inch thick round disks.
Roll larger ball of dough from center outward with steady pressure on a lightly floured work surface (or between two sheets of wax or parchment paper) into a circle 2-inches wider than pie plate for the bottom crust. Fold the dough in half, and then into quarters and carefully place the dough in the pie pan and carefully unfold the dough easing it into pie plate.
Trim edges of dough even with outer edge of pie plate. Fill unbaked pie crust according to recipe directions.
Roll out smaller dough disk. Transfer dough carefully onto filled pie. Trim edges of dough leaving a 3/4-inch overhang. Fold top edge under bottom crust. Press edges together to seal and flute as desired. Cut slits in top crust or prick with fork to vent steam.
Bake according to specific recipe directions.