3/4 cup granulated sugar
2 tablespoons finely grated lemon zest (about 2 lemons)
2 (9 1/4 by 10-inch) sheets puff pastry (about 9 ounces each), thawed
1 tablespoon unsalted butter, softened
1/2 cup yellow sanding or white granulated sugar, or a combination (see Cook's Note)
Sanding sugar has a slightly larger crystal and is used to decorate cookies. It can be found both in many supermarkets or specialty stores.