Place the flour and salt in a large bowl and whisk to combine.
Cut the cold butter into 1/4-inch slices and add to the flour mixture, tossing to coat.
Stir in the cold water until a thick dough forms.
Gather the dough into a ball, flatten it into a disk-shape, and wrap in plastic wrap.
Chill for 1 hour in the fridge, or 20 to 30 minutes in the freezer.
Unwrap the dough, dust the work surface with flour, and roll the dough into a rough rectangle shape.
Fold the dough in thirds, like a letter.
Turn 90 degrees, roll and fold again.
Repeat about 2 to 4 times, wrap the dough in plastic wrap, and chill for 2 hours or overnight.*