You will need:
1 large Granny Smith apple
1 T cinnamon
2 T brown sugar
Preheat your oven to 225 degrees F.
Use a mandoline slicer to cut the apple into very thin slices.
Dip each apple slice in the mixture, coating both sides.
Lay apple slices on a parchment lined baking sheet.
Bake for 1 hour, flip slices over, and bake for 1 more hour.