Ingredients

1 1/2 sticks butter, very cold or even frozen
3 cups (384 g) all-purpose flour
1/2 tsp kosher salt (1 teaspoon if using unsalted butter)
1 tablespoon sugar
1/3 cup very cold vegetable shortening
about 1/2 cup ice water

Directions

Makes two crusts (or a bottom and a top) and these will be large enough to use a deep dish pie plate.

Dice the butter and put it in the freezer while you prepare the flour mixture. Place the flour, salt, and sugar in the bowl of a food processor fitted with a steel blade and pulse a few times to mix. Add the shortening and mix a good 30 seconds. This will coat all the flour and help prevent gluten formation. Finally add the frozen butter cubes and pulse 8 to 12 times, until the butter is the size of peas. With the machine running, pour the ice water down the feed tube and pulse the machine until the dough begins to form a ball. Dump out on a floured board and roll into a ball. This will look really dry but if it holds its shape when squeezing a clump together, it's probably good to go. Wrap tightly in plastic wrap and refrigerate for 30 minutes to allow all the flour to hydrate.

If you don't have a food processor or just prefer to not use it, you can use a pastry cutter to manually break up the butter and shortening.

Cut the hydrated dough in half. Roll each piece on a well-floured board or pastry mat into a circle, rolling from the center to the edge, turning and flouring the dough to make sure it doesn't stick to the board. You're looking for about 1/8" thickness, about the height of two stacked quarters. Fold the dough in half, place in a pie pan, and unfold to fit the pan. Let the dough fall into place in the pan, don't press the dough to fit else it will stretch and be an irregular thickness.
Repeat with the top (or second) crust. Trim with scissors or shears leaving 1/2" overhang and fold under to make a thicker bead for the fluting.

Note on fluting the edge: Create flutes by using your thumb and forefinger on your right hand (inside the circle) and your left thumb (outside the circle) and press the flutes in a regular pattern around the perimeter.

Round shape trick: When you cut the dough in half you'll have a non-circular shape. Trim the half-moon shape into something closer to a circle and put the scraps in the middle and press them in. Now you can roll it out to a circular shape a bit easier.