Stir together flour and salt in a mixing bowl. For shortening lard is traditionally used, but we use butter or margarine. Cut in the shortening until the pieces are the size of small peas. This is most easily accomplished using a pastry blender, or you may use a fork.
Sprinkle the ice water over the mixture one tablespoon at a time, gently tossing with a fork. Push the mixture against the side of the bowl. Repeat with additional individual tablespoons of ice water until all the dough is moistened and the dough forms into a ball.
Divide the dough in half and flatten each half with your hands into a disc. Place the disc on a lightly floured surface, and using a rolling pin dusted with flour, roll out the dough from the center to the edges to form a circle about 12 inches in diameter.
Fold the circle of dough in half and lift onto the pie tin covering half the pie tin. Carefully bring the folded half up and over to cover the rest of the pie tin. Try to avoid stretching the dough so it remains a uniform thickness.
Trim the pastry so about one half inch beyond the edge of the pie tin and fold the extra dough under to build up the edge. This bottom pie shell is ready for your ingredients. After the ingredients have been added, repeat the procedure for the top crust.
The top and bottom crusts can be sealed by pressing with a fork to flute the edge all the way around the pie. You can also flute the edges for a single crust pie.
If you are baking an pie crust empty for use in a custard pie, for example, you should generously prick the crust with a fork. Prick all around the bottom of the pie tin where the bottom and sides of the pie tin intersect. Bake the empty pie crust in a preheated 450 ° F oven for about 10 to 12 minutes.