Peel and cut each banana in half—not lengthwise, but as if you were splitting a whole banana with someone so you each get half of the banana. Set aside.
Combine the oil, cinnamon, and brown sugar to a large mixing bowl.
Add the banana pieces to the bowl and gently toss to coat them all.
Preheat the air fryer to 375 F.
Take out the basket and place the air fryer liner inside the basket.
Use tongs to place the banana pieces inside the air fryer in a single layer. Don’t stack the pieces. You may have to work in rounds depending on the size of your air fryer.
Cook for 10 minutes.
Take out the basket. Gently turn the bananas with your tongs. With a pastry brush, coat the bananes in the basket with the cinnamon/oil mixture left in the bowl.
Cook for another 5 minutes.
Take out the basket. Let them rest for 2 minutes because they will be very hot.
With your tongs, take out the bananas to plate them. Then enjoy!