In a medium-size mixing bowl, use a whisk to sift together flour and salt.
Use a pastry cutter, 2 knives or a food processor to cut butter and shortening into flour until it resembles peas.
Add 7 Up mixing until the dough comes together.
Turn out onto a lightly floured non-stick surface. Divide in half or into thirds, then form into disks. (You may yield Two 10 inch pie crusts or three 8-9 inch pie crusts, divide according to how you plan on using it.)
Chill for at least 30 minutes or until firm.
To use: On a lightly floured non-stick surface, roll chilled dough into desired size. Press into pie plate. Flute edges using thumb and forefinger method or press with the tines of a fork.
May be blind baked and filled or used as the basis for pies and quiche with baked fillings. (See Cook's note for how to blind bake)