Put the tomatoes in a pot, chop them up a little and boil them down for 15-20 minutes. Clean, clean and slice the mushrooms. Add to the tomato puree. Wash the chicken filet, dab dry and cut into strips.
Heat the fat in a frying pan. Fry the meat for 3-4 minutes while turning, remove. Peel onion and garlic. Dice onion finely and sauté lightly in the frying fat. Add tomato puree and mushrooms.
Press the garlic through a garlic press. Wash the rosemary, pluck the needles from the stalks and chop finely. Season sauce with salt, pepper and rosemary. Cut the ham into strips, add and simmer everything for about 10 minutes.
Cook the spaghetti in plenty of boiling salted water for about 10 minutes until al dente. Wash and chop parsley. Chop cheese into shavings. Drain spaghetti and let it drain. Pour sauce over the spaghetti and sprinkle with parsley.
Pass the cheese with the spaghetti.