- 2 sticks unsalted butter
- 1 cup brown sugar
- 1 tablespoon cinnamon
- 1 teaspoon nutmeg
- 6 apples (such as Cortland, Rome or Granny Smith), peeled, quartered, cored and rubbed with lemon juice to prevent them from discoloring
- 1 sheet homemade or prepared puff pastry
- Flour, for rolling
- Preheat oven to 350 degrees F. In a 9 or 10-inch cast-iron skillet, melt 1 1/2 sticks butter over medium heat. Stir in sugar and spices, bring to a slow boil and cook, stirring, until mixture is a smooth caramel-colored sauce. Fit in apple quarters, round-side down; reduce heat to low.
- On a lightly-floured work surface roll out puff pastry until it is 1-inch in diameter larger than skillet. Prick all over with a pastry docker or with tines of a fork. Dot tops of apples with remaining 1/2 stick butter. Fit pastry round carefully over apples, tucking in edges. Transfer to oven and bake 25 minutes, or until pastry in golden brown.
- Remove skillet from oven. To unmold, loosen pastry around edges with a small, sharp knife.
- Invert a serving plate over top of pan. Using oven mitts, hold both pan and plate and in one motion, flip pan upside-down and set down. Tap bottom of pan gently to make sure tart is released. Lift off pan and serve warm or at room temperature.