In a large bowl, whisk together flour and salt. Add cold butter, and toss with your hands until butter is coated in flour. Using a pastry blender or your hands, work butter into flour mixture until butter pieces are quarter-size. Add ¼ cup (60 grams) ice water, and toss until flour is hydrated and a dough begins to form. (Mixture may appear crumbly. It should be moist and hold together when pinched.) Add more ice water, 1 tablespoon (15 grams) at a time as needed, until dough comes together when pressed. (Be careful not to add too much water.)

Turn out dough, and press into a flat square. Wrap tightly in plastic wrap, and refrigerate for at least 30 minutes or up to 2 days.

Turn out dough onto a lightly floured surface, and roll into a 10-inch square. Fold dough in half; fold in half again. (This mimics lamination.) Wrap in plastic wrap, and refrigerate for at least 30 minutes or up to 3 days, or freeze for up to 6 months. Let frozen dough thaw overnight in refrigerator before using.