Finely dice the onion and garlic, cut the ham into fine strips. Fry everything briefly in the pan. Meanwhile cook the pasta until al dente. Preheat the oven to 180 ° C.
Add tomato sauce and chunky tomatoes and bring to the boil for about 5 minutes, season to taste. Drain the pasta and mix with the sauce. Dice the mozzarella. Put the pasta in a baking dish and spread the diced mozzarella between the pasta. Sprinkle with grated cheese and bake for about 25 minutes.
I put aluminum foil over the baking dish so that the cheese doesn`t turn too brown right away. After about 20 minutes, remove the aluminum foil so that the cheese is only slightly browned.