Cut the butter into small chunks (1/4 to 1/2 Tablespoons in size). Place the butter and the shortening in the freezer to make them very cold. (See Note 2).
12 Tablespoons unsalted butter, 1/3 cup vegetable shortening
Prepare your ice water. Set aside.
1/2 cup ice water
Put the flour, salt, and sugar in the food processor. Pulse a few times to combine.
3 cups all purpose flour, 1 Tablespoon sugar, 1 teaspoon kosher salt
Add the butter and shortening to the flour. Pulse around 12 times until the butter is still in clumps approximately the size of corn kernels.
Continue pulsing while pouring the ice water through the food processor feed tube and continue pulsing until the dough forms a ball with most of the dough.
Remove the dough from the food processor, press together as needed, and wrap in plastic wrap. Refrigerate for 30 minutes.
Cut the dough in half and roll out each half on a well floured surface to your desired size and thickness as needed.
Gently lift, or fold over a rolling pin, and place in the pie dish. Continue with your pie recipe.
Ice water should be measured for the water used itself, not including the ice. The ice is just to make it cold. Measure when you are pouring it as melting ice will add to the water you use if you measure too early.
It is very important for the butter and shortening to be cold. Chill in the freezer at least 10 minutes, or have them in the refrigerator for at least 1 hour before using. You do not want them to be frozen, though.