Cut the old bread or rolls into cubes and soak them covered in water. When the bread is completely soaked, take it out and squeeze it out well. (Tip: take 2 cutting boards, press them both together with some of the wet bread in between).
Peel and finely chop the onion and garlic. Wash and chop the parsley. Sauté the onion in a little butter in the pan until translucent, mix in the garlic and finally the parsley. Remove the mixture from the heat and set aside. Hard boil two eggs.
Mix the minced meat with the onion, garlic and parsley. Mix the eggs, nutmeg, salt and pepper, squeezed bread and mustard well into a meat batter. To taste.
Put half of the meat dough in a suitable pan greased with butter. Make a well in the middle and place the two hard-boiled eggs (peeled) in it. Cut a mozzarella into small pieces and distribute it in the hollow. Place the other half of the meat batter on top as a lid. Smooth out with wet hands and shape into the roast. Cover with bacon like tiles. Bake in the oven at 200 ° C top / bottom heat.