1/4 cup + 2 Tbsp oat flour (or use more all-purpose flour)
3/4 tsp salt
3/4 tsp sugar
6 Tbsp cold vegan butter, cut into 1/2″ cubes (I used Earth Balance)
6 Tbsp vegetable shortening
5 Tbsp ice water
See video here (ingredients amounts differ, but the process is the same).
Fill a small bowl with water and add a couple ice cubes.
Combine the flours, salt, and sugar in a large bowl or the bowl of a food processor. Add the cold butter and pulse* a few times to break the butter up a bit. Add the shortening to the bowl and pulse again about 10 times until the butter and shortening pieces are about the size of peas.
Measure 3 Tbsp water into the food processor and pulse a couple times to mix. Add the remaining 2 Tbsp and pulse just until the crust sticks together when pressed between your fingers.
Dump the pie dough out onto a sheet of plastic warp. Gather all the bits and smoosh into a ball, then into a disk. Wrap in the plastic wrap and refrigerate 30 minutes.
Place the wrapped disk on a large smooth surface (cutting board, smooth countertop, etc). Unwrap, but leave the dough on the plastic. Place another large piece of plastic wrap on top of the dough so that the dough is sandwiched between the two pieces.
Use a rolling pin to roll the dough out into a 13″ diameter circle (it may go beyond the plastic wrap a bit).
Generously grease a 9″ pie dish.
Remove the top piece of plastic wrap and invert the crust into the pie dish. Carefully remove the other piece of plastic wrap, then fit the crust into the pie dish.
Lightly press the dough around the edge of the pie pan, then use scissors to cut excess dough from the edge, following the edge of the pan.
Fold the dough over to make a double-thick rim of the crust. Use three fingers to make the crimp along the edge. For clarification of the last two steps, please see the video!
I highly recommend using the Earth Balance butter sticks. They perform much better in baking than the tub butter
You can use all AP flour instead of the oat flour, but I’ve found that the little bit of oat flour makes the crust more flaky and gives it a better flavor, so if you have it then use it!