So I have been convinced: you can use just butter, forget the shortening, and still get a flaky pie crust. The key? COLD COLD COLD butter. Use frozen butter, dice it, refreeze it if it warms up, do not over process it, and keep it cold when rolling it out, refreezing if necessary in the middle of rolling. Refrigerate it while you prepare the filling.
Ingredients (makes enough for a bottom and top crust for a 9 inch pie, or for two bottom crusts or two 9 inch tarts)
2 1/2 cups flour
1 three-finger-pinch salt
(1 Tbs. sugar - optional)
2 sticks COLD COLD COLD butter, diced
1/4 cup give or take of ice water
For a tart, add 1 Tbs. sugar per cup of flour.
In food processor, combine flour and salt. Add diced butter and pulse until clumps form. DO NOT OVER PROCESS! There should be pea size pieces of butter and some smaller pieces. Add ice water slowly, pulsing just until moist crumbs form. Turn out onto a surface and form into 2 disks, 5 to 6 inches in diameter. Wrap in plastic wrap and refrigerate at least 1 hour. Can be frozen for up to a month.
When you are ready to roll the dough out, use a lot of flour to cover the work surface, the top of the dough, and the rolling pin. Roll out from middle of disk, pushing away from you. Rotate a quarter turn and do push from middle, rolling away from you. Continue in this manner until you have an 11 inch round. Gently fold dough into quarters and unfold in pie plate (or gently roll onto rolling pin and unroll again into pie plate). Trim so you have 1 inch overhang. Fold dough under to make the edge flush with the edge of the pie plate. Crimp, using thumb and forefinger of one hand and forefinger of the opposite hand to form ridges. Refrigerate or freeze dough before baking.