Soak rolls in cold water. Peel onions. Chop 1 onion finely. Wash the basil, dab dry and cut the leaves into fine strips, except for some for garnishing.
Squeeze the bread roll and knead with minced meat, egg, chopped onion, half of the basil, mustard, salt and pepper. Form an oblong loaf from the mixture and put it in an ovenproof dish with the oil.
Roast in the preheated oven (electric: 200 °C/ gas: level 3) for 50-60 minutes. In the meantime, clean and wash the broccoli and cut into florets. Cook in little boiling salted water for 8-10 minutes. Pour onto a sieve and drain.
Clean the tomatoes, wash and pat dry. Roughly dice 125 g tomatoes, cut the rest into slices. Cut the rest of the onions into slices as well. Drain mozzarella and cut into slices.
10 minutes before the end of the frying time, spread tomato cubes, mozzarella and about half of the remaining basil on the roast. Pour in broth and cream and finish frying. Heat the fat in a pan and fry the onion slices until golden brown.
Add tomato slices at the end and braise briefly. Fold in the broccoli florets, warm them up and season with salt and pepper. Put the roast on a preheated plate, arrange the vegetables all around and garnish with basil.
Pour frying stock into a pot, bring to the boil and add sauce thickener while stirring, bring to the boil again briefly. Add the remaining basil to the sauce and season with salt and pepper. Serve the sauce separately with the meat.
Ribbon noodles taste good with it.