In a large mixing bowl stir together flour and salt.
Add the butter slices to the flour mixture; toss till butter slices are coated with the flour mixture and are separated.
Pour ice water over the flour mixture. Using a spoon, quickly mix (butter will remain in large pieces and flour will not be completely moistened).
Turn dough out onto a lightly floured surface. Knead dough 10 times by pressing and pushing dough together to form a rough-looking ball. Shape dough into a rectangle (dough still will have some dry-looking areas). Make the corners as square as possible. Slightly flatten dough.
Working on a well-floured surface, roll the dough into an 18x15-inch rectangle. Wrap dough with plastic wrap. Chill for 20 minutes.
To use dough, cut in half and roll out again then use as needed.