Heat a large skillet over medium heat with 1/2-1 inch of oil.
In a large mixing bowl, combine the flour, salt and pepper, cayenne, paprika, and garlic together. In another mixing bowl, combine the egg, buttermilk, and barbecue sauce.
Place each onion ring in the liquid egg mixture, dredging it, allowing excess to drip off of it, and then directly placing it in the flour mixture, being sure to coat the entire ring.
Quickly place each ring in the hot oil and allow to turn a golden brown (approx. 1-3 minutes each side). Once golden, flip the onion ring over and allow the second side to brown.
Carefully remove the onion ring from the skillet and place on a paper towel-lined baking sheet.
Allow to sufficiently cool before enjoying it messy!