Preheat oven to 450°. Whisk together sugar, flour and nutmeg; set aside. On a lightly floured surface, roll one-third of pie dough to a 1/8-in.-thick circle; cut into 2×1-in. strips. Layer a deep 12-in. enamel-coated cast-iron skillet or ovenproof casserole with half the strips; sprinkle with half the sugar mixture. Dot with half the butter….