Cook sausage links according to package directions; drain, cut into 1/4-inch slices and set aside. In a large saucepan, sauté onions in oil until tender, about 3 minutes. Add potatoes, carrots and continue to cook for about 1 minute. Stir in tomatoes, water, pasta, zucchini and sausage. Bring to a boil; reduce heat. Cover and simmer for 6-8 minutes or until pasta is tender. Spoon stew into serving bowls and sprinkle with Parmesan cheese. Serve.