Then you simply dip your onion rings in the batter and coat completely, and then dip the onion into the breadcrumbs and do the same (I usually form a little mound over the ring and then remove). Place your rings on a parchment lined baking sheet, air fryer tray (these don’t seem to drip much or at all), or silicon baking sheet (I like this one).
While the oil is heating, mix flour, cornmeal and salt together in a pie plate or other wide dish. Pour the onions and buttermilk into a strainer, letting the buttermilk run off. Using tongs, place the onion rings in batches into the cornmeal mixture until they are coated. Still using the tongs, carefully place the onion rings into the hot oil. Dip each onion ring into the all-purpose flour, then the egg mixture, then the breadcrumb mixture, then place it carefully on a lined baking tray. Spray each onion ring with rapeseed oil making sure that every part is evenly covered. Bake at 400 F for 20 minutes, flipping all the onions after 10 minutes. Preheat the air fryer to 370°F. Once it is preheated, coat the basket with cooking spray. Place onion rings in a single layer in the air fryer basket, and cook in batches at 375°F for 5 minutes. Flip and spray again with oil, then cook until golden brown and crispy on both sides, for another 3-5 minutes. 3XQ2.