I love how they turn out perfectly crispy and sweet, w/ caramelized onion inside. Easy to bite off without pulling the onion out. My whole family loved them. 
Ingredients:
1 large onion. Sweet yellow onion or Vidalia kind.
1/2 cup all-purpose flour
1 Egg, beaten
1/2 cup buttermilk
1 tsp smoked paprika
1/2 tsp salt or to taste
1/4 tsp pepper or to taste
1 cup Breadcrumbs. I used a mix of Seasoned breadcrumbs and Panko. Both work well. If used unseasoned breadcrumbs, add salt and pepper to taste.
Spray oil
Instructions:
Clean the onion and slice it in approximately 1/4 inch rings. Separate the rings from each other. Pick out the largest ones. Medium size rings are good too. Reserve the small rings for other recipes.
In a first medium bowl, combine the flour, salt, pepper and paprika. In a second medium bowl, beat the egg, add buttermilk and salt to taste.
In a third medium bowl pour breadcrumbs. Working one onion ring at a time, coat each one in egg mixture, then flour mix, then back to egg mixture and then finally in breadcrumbs.
Arrange the breaded onion rings in the air fryer basket/sheet.tray and give them some space so they do not touch each other. Depending on the size and shape of your air fryer, fry onion rings in batches. My Cuisinart air fryer oven basket comfortably fits 9 large onion rings at a time.
Preheat air fryer to 400F/200C for 2 minutes. Air fry mode at 400F/200C and fry for 5 minutes. Open air fryer, flip each onion ring on the other side, set the air fryer to 350F. Gently spray onion rings with oil spray and fry for an additional 3-5 minutes or until the breading is crispy, crusted and golden brown.
Enjoy while they are freshly crisp. Dip in your favorite sauce/ketchup. I used two dips: ketchup and homemade chipotle mayo. Delicious!
Store leftovers (if any) in the refrigerator and reheat for a minute until crispy again.
