Peel the onion, cut into fine cubes, and sauté in butter over medium heat for roughly 5 minutes until translucent. Cool for 2 minutes, then mix with the minced meat.
Add the eggs, mustard, breadcrumbs, dried parsley, diced bacon, Maggi, salt, and pepper to the minced meat mixture. Mix until well combined. If desired, add 1 teaspoon Worcester sauce.
Shape the mixture into balls and flatten them slightly.
Heat clarified butter or oil in a pan over medium heat. Fry the meatballs on both sides for 8-10 minutes until cooked through and crispy.