Mix the 3 dry ingredients together.
Using a pastry blender, cut the shortening into the dry ingredients. Mixture should be like coarse cornmeal and not have large clumps of shortening.
In separate bowl, beat together vinegar, egg and cold water.
Make a well in the dry ingredients.
Add liquid mixture, tossing with a fork until all dry ingredients are moistened.
With hands, form dough into 4 balls. Place all 4 balls into a bowl.
Cover and chill at least 15 minutes. (dough can be left in refrigerator up to 3 days or frozen)
Roll out dough onto lightly floured surface in a large circle of even thickness. Make sure dough does not stick to the surface by picking up dough, turning it and/or using a small amount of additional flour.
Dough should be about 1/8” thick and 2” larger than an inverted pie pan.
Use as directed for single or double crust pies.