Preheat your oven to 200 degrees and line cookie sheets with parchment paper.

Using a potato slicer (that's all I had on hand that would work for this), slice your apples one by one.

Lay them evenly across your cookie sheet and sprinkle liberally with cinnamon.

Bake at 200 degrees for 3 hours, then turn the oven off and keep them in the oven for another hour.