Soak the buns. Peel onions. Cut one into rings, dice 2 finely. Wash the parsley and chop except for something to garnish.
Knead the ground pork, squeezed bread roll, egg, half onion cubes, parsley, Italian herbs and mustard. Season with pepper and possibly salt. Form 8-10 meatballs from it. Fry in hot oil for 6-7 minutes on each side. Add onion rings at the end and fry until crispy
Drain mushrooms well. Fry the rest of the onion cubes in hot fat. Add mushrooms and fry well. Deglaze with cream and about 1/4 l water, stir in broth and simmer briefly. Bind with sauce thickener and season to taste. Serve everything. Garnish with the rest of the parsley and possibly tomato. Noodles, French fries or boiled potatoes taste good with it