Peel and slice the onions into rings about half an inch thick. Rinse briefly in cold water if you prefer a milder flavor, then dry thoroughly with a clean towel.
Set up your coating stations: in one bowl, whisk the eggs; in another, combine panko breadcrumbs with paprika, salt, and pepper.
Dip each onion ring into the beaten eggs, allowing any excess to drip off, then coat it evenly in the seasoned breadcrumb mixture, pressing gently to adhere.
Place the coated onion rings on a wire rack set over a baking sheet, making sure they are spaced apart to allow air circulation for even crisping.
Lightly spray the tops of the onion rings with oil to help them crisp up in the oven.
Bake in a preheated oven at 220°C (425°F) for 15 to 20 minutes, flipping the rings halfway through and spraying again if needed, until they are golden and crackling.
Check for doneness: the coating should be a deep golden color and feel crispy to the touch, with a crackling sound when tapped.
Remove from the oven and let rest on the rack for a couple of minutes to firm up and retain their crunch.
Serve immediately with your favorite dipping sauce, enjoying the warm, crispy, sweet onion flavor.
