Preheat oil in a deep fryer or heavy-bottomed pot to 350°F (175°C), keeping the temperature steady with a thermometer.
In a bowl, combine ground beef, Worcestershire sauce, garlic powder, onion powder, salt, and pepper.
Mix gently without overworking. Slice onions into thick rings and press a small portion of the beef mixture into each center. Add shredded cheddar before sealing.
Set up a breading station with flour, beaten eggs, and breadcrumbs.
Dredge each stuffed onion ring in flour, dip in egg, then coat with breadcrumbs, pressing so crumbs stick.
Fry 3–4 minutes, turning once, until golden and crispy. Drain on a paper towel-lined plate.
While still hot, sprinkle with crumbled bacon and extra cheese. Serve warm with your favorite dipping sauce.