Rough Puff Pastry

Push butter 1 stick at a time through feeding tube of a food processor fitted with the medium shredding disc to grate (you need to use a bit of force and work quickly, but the food processor can handle it; it’s okay if the ends of each stick don’t make it through). You can also grate frozen butter on the large holes of a box grater; grip butter with a paper towel and work quickly, then freeze again 10 minutes. Transfer grated butter to a medium bowl and toss gently with 2 Tbsp. flour until coated. Transfer to freezer to keep cold.

Whisk sugar, salt, and 2½ cups flour in a medium bowl. Add half of frozen butter mixture and toss to coat (return bowl with remaining butter to freezer).

Stir milk and ⅓ cup ice water in a measuring cup and drizzle over flour mixture, mixing with a fork until shaggy pieces form. Knead in bowl a couple of times with your hands to form a shaggy dough. Transfer all of the large clumps of dough to a work surface, leaving smaller pieces behind. Drizzle 1 Tbsp. ice water over remaining flour mixture in bowl and knead again to bring together. Add to dough on work surface. Knead dough a couple more times to form a single mass (it’s okay to work dough a bit more than you would for pie dough); the flour should look mostly hydrated with only a couple of dry spots remaining. Press into a 1"-thick square and wrap tightly in plastic. Chill 20–30 minutes.

Roll dough on a lightly floured surface to a 18x6" rectangle, dusting underneath with more flour to prevent sticking. Place dough on work surface so short side is facing you. Now imagine that it’s divided into three 6x6" squares stacked in a column.

Sprinkle one-quarter (about 1½ oz.) of remaining butter mixture in a single layer inside center square. Fold lower square over butter, lining up outside edges. Sprinkle about one-third (1½ oz. again) of remaining butter over newly folded dough. Fold upper square down and over butter to form a neat 6x6" packet (think of folding a letter; the center does not move).

Press dough firmly together on all sides to seal. Rotate dough package 90° counterclockwise so top flap opening is on your right. Roll out dough, dusting with flour as needed, to a 18x6" rectangle again. Repeat folding process, incorporating all remaining butter. Press firmly to seal, wrap in plastic, and chill 20 minutes and up to overnight.

Roll out dough on a lightly floured surface to 18x6" rectangle again. Fold in thirds as before (but without incorporating any butter). Rotate 90° counterclockwise as before and roll out to a rectangle again. Repeat folding process one more time. Wrap in plastic and chill at least 20 minutes. Dough is now ready to be rolled out and used.

Do Ahead: Rough puff pastry can be made 2 days ahead; keep chilled, or freeze up to 1 month. Thaw overnight in refrigerator before using.