In a mixing bowl, combine the flour, salt and Crisco. Cut the Crisco into the flour with a pastry blender or a fork until mixture is crumbly.
In a small dish, add yolk, vinegar,and water; blend well with a fork. Add liquid to flour mixture and blend well with a fork until dough is thoroughly incorporated then use your hands to work it together to form a ball.
Divide the dough in half to make 2 balls.
Place one ball of dough between 2 sheets of waxed paper and roll it out with a rolling pin; rolling it a little larger than the size of your pie pan.
Remove top piece of waxed paper and then gently flip over the dough onto your pie pan. Remove waxed paper and gently shape the dough into the pie pan. Trim excess dough off.