Put pot of water on to boil pasta. Add pasta to boiling water, and cook as instructed
Coin zucchinis and sausage and set aside. Cut up onion.
Sauté sausage in large pan until cooked and set aside.
Sauté zucchini and onions in olive oil until onions and zucchini are tender.
Add in sausage and balsamic vinegar to taste.
Combine drained, cooked pasta into the sautéed zucchini, onions, and sausage.
Top with parmesan cheese (optional)