Soak the stale bread roll in lukewarm milk. Add an egg to the mince, the soaked and well-squeezed bread roll and the onion cubes that have been steamed in a little fat and mix well. Add tomato paste, medium hot mustard, sweet mustard, pepper, salt, paprika, washed and finely chopped parsley and a pressed clove of garlic. Knead the mixture well and season to taste.
Shape the meatballs, roll them in breadcrumbs and fry them in a hot pan with rapeseed oil and butter on a not too high heat for about 30 minutes, turning several times.