Remove seeds by popping them out by hand or using the end of a sharp knife to gently pop them out.
Lay apples in a single layer on baking sheets that have been covered in parchment paper.
Lightly sprinkle apple slices with cinnamon and sugar.
Bake at 225 degrees for 2 ½ hours, flipping the apple slices over after 1 hour.
Turn the oven off, but keep the apple chips inside the oven. The chips will crisp as they cool.
Video
Notes
If you use a mandolin to slice your apples, they may bake more quickly. Flip slices over after 30 minutes, then keep an eye on them after 60 minutes.If making more than one tray of apple chips, rotate the baking racks midway for even baking.