Slice apples into rings 3/16 to 1/4 inch thick. (Optional: sprinkle to taste with cinnamon and/or sugar). Dry 4-10 hours at 135° until leathery to crisp. (Option: for whiter apple rings, drop slices into 1 cup water and 2 tablespoons lemon juice. Pat dry before drying). Natural sugar: Powder dried apples in blender. Sprinkle on cereal, toast, ice cream, etc.