Preheat oven to 225 degrees.
Peel and core the apples and slice thinly.
Place sliced apples on parchment lined baking sheets.
Sprinkle some cinnamon and sugar on the apple slices.
Bake the apples for 1 hour and then flip the apple slices.
Sprinkle with some more cinnamon and sugar.
Return to oven for 1 more hour.
Turn off oven and keep apples in turned off oven for 1 more hour.
Remove from oven and enjoy!