Boil up plenty of salted water for the pasta. Wash and coarsely dice the tomatoes. Peel and chop garlic. Cook pasta in salted water according to package instructions. Wash basil, shake dry, pluck and cut into strips.
Tear up the ham slices.
Mix tomatoes, garlic, basil and ham with lemon peel, juice and oil. Season to taste with salt and pepper. Cut mozzarella into cubes. Drain the pasta and put it back into the pot.
Add the tomato mixture and serve immediately with mozzarella.