01 - Wash apples thoroughly and remove cores using an apple corer or sharp knife. Slice apples crosswise into thin rounds approximately 1/8 inch thick using a mandoline slicer or sharp knife for uniform thickness.
02 - Pat apple slices dry with paper towels to remove excess surface moisture, which helps achieve better crispiness during cooking.
03 - Place apple slices in a single layer in the air fryer basket, ensuring no overlap. Cook in batches if necessary to maintain proper air circulation for even crisping.
04 - Lightly spray or brush slices with oil if desired. Sprinkle ground cinnamon evenly over all apple slices. Add optional sugar at this stage if using.
05 - Cook at 325°F for 12 to 15 minutes, flipping all slices halfway through after 7 minutes. Watch closely during the final minutes to prevent over-browning.
06 - Remove chips when golden and crisp. Transfer to a wire rack to cool completely, as chips will continue to crisp during cooling. Store in an airtight container for up to 5 days.