Freeze cold butter until firm, 15 to 20 minutes.

In the bowl of a stand mixer fitted with the paddle attachment, beat cold butter, flour, and salt at low speed just until butter is coated with flour. With mixer on low speed, add ½ cup (120 grams) ice water in a slow, steady stream, beating just until dough comes together, about 1 minute, stopping to scrape bottom and sides of bowl and turn dough to hydrate evenly. (There will still be large pieces of butter. It is OK if a few dry bits remain.)

Turn out dough onto a lightly floured surface, and roll into a 7-inch square. Wrap in plastic wrap, and refrigerate for 45 minutes to 1 hour.

On a lightly floured surface, roll dough into an 18x10-inch rectangle, lightly flouring surface and top of dough as needed. Fold dough in thirds like a letter. Rotate dough 90 degrees; roll into an 18x10-inch rectangle, and fold in thirds like a letter. Repeat procedure for a third and final turn. Wrap dough in plastic wrap, and refrigerate for at least 1 hour. (If at any point the butter is too soft after a fold, wrap in plastic wrap, and freeze until butter is firm again, checking every 5 minutes.)