Preheat oven to 200 degrees fahrenheit.
Add the sliced apples to a large bowl; then coat the apples with the cinnamon and/or sugar.
Spray a baking sheet with cooking spray and line the apples flat on the pan. You may need to use two pans so that they are not overlapping.
Bake 2-3 hours until the chips are dry yet still soft. Allow to cool completely before placing them in an air tight container for up to 4 days (if they last that long!).