Cremini and Zucchini Spaghetti with Parmesan Garlic Bread

Bring a large pot of salted water to a boil. Wash and dry all produce. Trim and dice zucchini into ¼-inch pieces. Dice mushrooms into ¼-inch pieces. Dice tomato into ¼-inch pieces. Halve, peel, and finely dice onion.