In a large bowl, whisk together flour, sugar (if using), and salt.
Grate cold butter and toss until evenly coated, place into freezer for 15 minutes. Use a pastry cutter, or two knives, cut butter into the flour mixture until fully incorporated.
Chill the mixture again for 10 minutes to keep the butter cold.
Remove from freezer and drizzle in ¼ cup ice cold water. Combine with a spoon, using your hands if needed to bring the dough together. If dry, add cold water one tablespoon at a time until you can form a ball.
Divide the dough in half and shape into two round, flat disks. Wrap with plastic wrap and refrigerate for about 2 hours.
On a lightly floured surface, roll the dough out with a rolling pin.