01 - Peel the bananas and cut them into thin, even slices about 1/8 inch thick using a sharp knife or mandoline slicer.
02 - In a small bowl, mix together the granulated sugar and ground cinnamon until evenly combined.
03 - Brush the banana slices lightly with melted coconut oil on both sides, then sprinkle the cinnamon sugar mixture evenly over both sides of each slice.
04 - Arrange the coated banana slices in a single layer in the air fryer basket. Work in batches if necessary to prevent overlapping.
05 - Air fry at 350°F for 10-15 minutes, flipping the chips halfway through cooking. Watch closely during the last few minutes to prevent burning.
06 - Remove from the air fryer and let cool on a wire rack. The chips will crisp up as they cool. Optionally sprinkle lightly with sea salt before serving.