Heat a greased 10-inch cast-iron skillet in a 350° oven 8 minutes or until hot. Arrange one-third of potato slices in skillet, and drizzle with one-third of butter; sprinkle with 1/4 teaspoon salt and 1/4 teaspoon pepper. Repeat layering procedure twice with remaining ingredients.
Bake at 350° for 1 hour; increase heat to 500°, and bake 5 to 10 more minutes or until browned. Invert onto a serving plate; garnish, if desired.