Crunchy and flavorful, these homemade onion rings are a delicious snack or side dish. Made with the Ninja Foodi air fryer, they are much healthier than traditional deep-fried onion rings. Simply dip the onion rings in a batter made with flour, spices, and buttermilk, then air fry until golden brown and crispy. Serve them with your favorite dipping sauce for a tasty treat.