In a large mixing bowl, whisk together the flour, salt, and sugar until evenly combined.
Add the cold butter cubes to the flour mixture. Using a pastry cutter or your fingertips, work the butter into the flour until the mixture resembles coarse crumbs with some pea-sized butter pieces remaining.
Gradually sprinkle 1/4 cup of ice water over the mixture, using a fork to gently toss and combine. Add more water, 1 tablespoon at a time, until the dough just holds together when pressed.
Turn the dough out onto a lightly floured surface and gently knead it a few times to bring it together. Divide the dough into two equal portions and shape each into a disc.
Wrap each disc tightly in plastic wrap and refrigerate for at least 1 hour, or until firm, before rolling out and using in your pie recipe.