Buy a jar of your favorite applesauce. Spray a baking sheet with cooking oil, or apply a thin layer with a paper napkin. Add optional ingredients to the applesauce. Pour the sauce onto the baking sheet, spreading to an even 1/4" thick.
Place in oven 120-140 degrees, door propped for about 5 hours. It's done when it peels off the pan, and doesn't look wet. Cut into 1/2" squares. Place them in a heavy duty zip-lock bag.
Pour enough water into bag to rehydrate the applesauce, adding more as necessary. Set aside while you prepare dinner.
Or to feel extra wild, just eat the apple chips straight from the bag; no water necessary.