Lemon-Sugar Galette

Directions

1. 1
   Preheat oven to 500°F with rack in upper third.
2. 2
   Roll out dough into a 15- by 12-inch rectangle on a lightly floured surface with a floured rolling pin. Transfer to a buttered 17- by 13-inch baking sheet and stretch to edges. Let stand 10 minutes.
3. 3
   Brush dough with butter, then stir together sugar and zest and sprinkle over dough. Bake, rotating sheet halfway through baking, until golden in spots and crisp, 7 to 10 minutes. Break into pieces.