01 -
Peel the onions and slice them into thick 3/4-inch rounds. Separate the rings and pair each large ring with a smaller ring that fits inside, leaving a gap for cheese.
02 -
Cut the mozzarella into strips that fit the gap between the paired onion rings. Pack the cheese between the rings, pressing gently so the pieces sit snugly.
03 -
Place the stuffed rings on a parchment-lined tray and freeze for 45-60 minutes, until firm enough to handle without shifting.
04 -
Mix flour, garlic powder, paprika, salt, and pepper in one shallow bowl. Whisk eggs with milk in a second bowl. Add panko to a third bowl.
05 -
Coat each frozen ring in seasoned flour, dip in egg, then press into panko. For a sturdier crust, dip again in egg and panko, pressing crumbs into the edges.
06 -
Heat oil to 350°F (175°C) in a heavy pot. Fry the rings in small batches for 2-3 minutes, turning once, until deep golden and crisp.
07 -
Transfer the rings to a wire rack and sprinkle lightly with salt. Serve hot with marinara or ranch while the mozzarella is melted.