Cheddar Pepper Palmiers

Toss Cheddar, Parmigiano-Reggiano, pepper, and salt in a bowl.

Sprinkle 1/4 cup cheese mixture onto a work surface. Unfold 1 pastry sheet and place over cheese. Using a rolling pin, flatten the dough into a 10-inch square, then sprinkle 1/2 cup cheese mixture all over top of pastry, pressing lightly to adhere. Fold sides of 2 ends to meet in center, then fold once more into center and press ends together. Wrap tightly in plastic wrap and chill until firm, about 1 hour (or freeze 15 to 30 minutes). Repeat with remaining cheese and second sheet of pastry.

While dough chills, preheat oven to 400F with racks in upper and lower parts of oven. Line 2 large baking sheets with parchment paper.

Working with 1 piece at a time (keep remaining chilled until ready to use), unwrap pastry and cut, seam side up, into 1/4-inch-thick slices, arranging them 1 inch apart on baking sheets. Bake, turning palmiers over and switching position of pans halfway through, until golden and pastry is cooked through, 18 to 22 minutes total. Transfer palmiers to rack to cool. Repeat cutting and baking remaining pastry on cooled sheets.

Make ahead: Dough can be assembled up to 3 days ahead. Palmiers can be baked 1 day ahead and kept in an airtight container at room temperature.