In a very large skillet cook onion, mushrooms, red sweet pepper, and garlic in hot oil over medium heat about 5 minutes or until onion is tender. Stir in undrained tomatoes, tortellini, water, wine, Italian seasoning, and black pepper. Bring to boiling; reduce heat. Simmer, covered, for 10 minutes. Stir in zucchini. Cook, uncovered, 5 minutes more or until zucchini is crisp-tender. Remove from heat. Sprinkle with Asiago cheese. Makes 4 to 6 servings.