1) Bring a large saucepan of salted water to the boil over a medium heat. Add the pasta and cook it according to the directions on the packet.
2) While the pasta is cooking, whisk together the balsamic vinaigrette, mayonnaise and sugar in a small bowl.
3) Drain the pasta well, transfer to a large serving bowl and allow it to cool. Add the tomatoes, mushrooms, olives, green pepper, salt, to taste, and the black pepper.
4) Pour the dressing over the salad and toss to combine. Sprinkle with the grated cheese, toss lightly and serve.