01 - 
                Whisk together buttermilk and egg in a shallow dish.
              
              
              
                02 - 
                Whisk flour, cornstarch, smoked paprika, salt, pepper, and garlic powder together in a separate shallow dish. Add breadcrumbs to a third shallow dish.
              
              
              
                03 - 
                Dredge onion rings in the flour mixture, then in the buttermilk mixture, then breadcrumbs. Set aside for 10-15 minutes until ready to fry. The longer sitting time allows the coating to absorb some of the liquid and get tacky, which helps prevent a lot of it from falling off while frying.
              
              
              
                04 - 
                Heat 1" of oil in a large cast iron skillet or other heavy duty pot like a dutch oven to 350°F to 375°F.
              
              
              
                05 - 
                Fry 3-4 onions rings at a time for 2-3 minutes without crowding the pan. Flip halfway through and only cook until the onion rings are light golden brown and crispy.
              
              
              
                06 - 
                Transfer fried onion rings to a wire rack set over a baking sheet to drain any excess grease and repeat with remaining onion rings. Serve immediately.