2Granny Smith applespeeled and cut into 1/2' slices
Instructions
Preheat the oven to 400 degrees F.
Roll out the puff pastry and cut a circle that's 1 ½ inches wider than the skillet you'll be using. Cut 4 slits in the center of the pastry circle. Store the dough in the fridge to keep it cold.
Place a cast-iron skillet over medium-low heat. Add the butter, and once it's melted, add the sugar. Stir and cook for about 2 minutes. Remove the skillet from the heat and arrange the apple slices around the outer edge of the skillet. Cook for 8-10 minutes. (The sugar mixture should be a light amber color.)
Remove from the heat. Then place the cold puff pastry over the skillet. Carefully push the sides of the pastry down, almost tucking them in to create a "lid" on top of the apples.
Bake for 20-22 minutes or until the top of the pastry is golden brown. Remove from the oven and place a wire rack over the skillet. Carefully flip the skillet over so the tart is on the rack. (There will be some drippage, so it might be a good idea to have a baking sheet to set the wire rack over.)
Cool until warm or room temperature. Cut into 6 slices and serve as is or with a scoop of vanilla ice cream on top.
Notes
If you only have unsalted butter on hand, add ⅛ teaspoon of salt in with the butter and sugar.
You may not need the full 2 apples. It depends on how big they are, so don't worry if you end up with extra slices.