On a cutting board, cut sausage links lengthwise into fourths, and then dice; set aside. In a soup kettle or Dutch oven, sauté onions, carrots and garlic in oil until tender, about 5 minutes. Add sausage, cook and stir for 2 minutes. Stir in tomatoes, consommé, water, parsley, basil and bay leaf. Bring to a boil; reduce heat. Cover and simmer for 20 minutes. Add zucchini and tortellini; simmer 10 minutes longer or until pasta is tender. Discard bay leaf. Ladle into serving bowls and sprinkle with Parmesan cheese, if desired.