Skip the deep fryer and make crispy homemade onion rings in the Ninja Air Fryer. Slice onions into rings, dip them in a batter made with flour, buttermilk, and spices, and then coat them in breadcrumbs. Air fry until golden and crispy. These homemade onion rings are a tasty side dish or snack that pairs well with burgers, sandwiches, or as a standalone appetizer.