Use this recipe when making our Deep-Dish Apple Pie.
Place flour, salt, and sugar in a food processor; process to combine. Add butter and process until mixture resembles coarse meal, about 10 seconds. Add 1/2 to 3/4 cup ice water in a slow, steady stream through the feed tube with the machine running, just until the dough holds together. Do not process for more than 30 seconds. Test dough by squeezing a small amount together; if it is still crumbly, add a bit more water.
Turn dough out onto a piece of plastic wrap. Press into a flattened circle and wrap in the plastic. Refrigerate for at least 1 hour before using.