1Preheat the air fryer to 180°C (350°F) for 5 minutes.
2In a large bowl, mix together the cooked chicken, mixed vegetables, rice or pasta, cream soup, milk, half of the shredded cheese, garlic powder, onion powder, salt, and pepper.
3Transfer the mixture to an oven-safe dish that fits in the air fryer (about 6-7 inches in diameter).
4In a small bowl, mix the breadcrumbs with melted butter and sprinkle over the casserole, then top with the remaining shredded cheese.
5Cover the dish tightly with aluminum foil and cook in the air fryer for 15 minutes.
6Remove the foil and cook for another 7-10 minutes, until the topping is golden and crispy.
7Check that the internal temperature has reached at least 165°F (74°C). Let the casserole rest for 5 minutes before serving.