Season the flour with paprika, 1 teaspoon granulated garlic, 1 teaspoon salt and pepper.
Add in milk and egg. Whisk together until well combined.
Dip the onion rings into the wet batter and then let the excess batter drip off.
Season the panko bread crumbs with remaining granulated garlic and salt. Dredge the onions in the panko until coated completely.
Fry, in batches, until golden brown and crispy. Remove from oil and place on a wire rack on top of a baking sheet. Sprinkle with salt and keep warm while frying the rest of the onions.