Prepare pasta according to package directions. Drain; rinse with cold water. Drain again.
Meanwhile, in a very large bowl, combine chopped tomato, broccoli, cauliflower, carrot, celery, sweet pepper, onion, mushrooms, olives, and garlic.
Add drained pasta to vegetable mixture. Add salad dressing; toss to coat. Sprinkle salad with parsley and Parmesan cheese. Toss again. Chill, covered, in the refrigerator for 4 to 24 hours. Stir before serving. Makes 16 side-dish servings.