Preheat your air fryer to 400F according to your manufacturers instructions.
Spray one side of one of the tortillas, and place the oiled side down in the basket or tray of the preheated air fryer.
Top with the shredded cheese, then any desired fillings such as chicken, beans, corn, or jalapenos.
Spray one side of the remaining tortilla and place it on top of the shredded cheese and fillings, with the oiled side facing up.
Place an oven safe metal trivet on top of the quesadilla to hold the tortilla down. Alternatively, you can spear several toothpicks through the layers to hold everything in place.
Cook in the air fryer for 4-6 minutes, or until the tortillas are golden and the cheese is melted and gooey. Optionally, you can flip at the halfway point to ensure even browning, but it isn't necessary if you just want to a quick meal.
Remove the hot trivet using a pair of tongs, and remove the quesadilla using a large spatula.
Place the quesadilla on a cutting board and allow to cool for 2-3 minutes before cutting into quarters with a pizza cutter or sharp knife.