Cook the pasta in boiling salted water according to the instructions on the packet. Mix pesto, vinegar, sugar and 4 tablespoons of water. Wash and halve the tomatoes. Wash, clean and roughly grate the zucchini.
Peel the onion and cut into strips. Cut mozzarella into fine cubes. Pour pasta into a sieve and rinse with cold water. Mix vegetables, cheese, dressing and noodles. Arrange and garnish with basil.