In a large bowl, with a pastry cutter, gradually work the Crisco into the flour for about 3 or 4 minutes until it resembles a coarse meal. In a small bowl, beat an egg with a fork and then pour it into the flour/shortening mixture. Add 5 tablespoons of cold water, 1 tablespoon of white vinegar and 1 teaspoon of salt. Stir together gently until all of the ingredients are incorporated.
Separate the dough into thirds. Form 3 evenly sized balls of dough and place each dough into a large Ziploc bag. Using a rolling pin, slightly flatten each ball of dough (about ½ inch thick) to make rolling easier later. Seal the bags and place them in the freezer until you need them. (If you will be using it immediately it’s still a good idea to put in the freezer for about 15 to 20 minutes to chill.)
When you are ready to use the dough to make a crust, remove from the freezer and allow to thaw for 15 minutes. On a floured surface roll the dough, starting at the center and working your way out. (Sprinkle some flour over top of the dough if it’s a bit too moist.) If the dough is sticking to the countertop use a metal spatula and carefully scrape it up and flip it over and continue rolling until it’s about ½ inch larger in diameter than your pie pan.
With a spatula, lift the dough carefully from the surface of the counter into the pie pan. Gently press the dough against the corner of the pan. Go around the pie pan pinching and tucking the dough to make a clean edge.