01 - Wash and core the apples. Using a mandoline slicer or sharp knife, slice the apples crosswise into thin rounds approximately 1/8 inch thick for uniform cooking.
02 - Pat the apple slices thoroughly dry with paper towels to eliminate surface moisture, which promotes better crisping during the air frying process.
03 - Place the apple slices in a single layer inside the air fryer basket, ensuring pieces do not overlap. Work in batches if necessary to maintain proper air circulation.
04 - Lightly spray or brush the slices with oil if desired, then sprinkle ground cinnamon evenly across all pieces. Add optional sugar at this stage for enhanced sweetness.
05 - Cook at 325°F for 12 to 15 minutes, flipping all slices after 7 minutes to ensure even browning. Monitor closely during the final minutes to prevent over-browning.
06 - Remove the golden, crisp chips from the air fryer and transfer to a wire rack. Allow to cool completely as chips will continue to crisp during cooling. Store in an airtight container for up to 5 days.