Bring lightly salted water to boil over high heat.
Heat olive oil in large skillet over medium heat. When hot, sauté onion and garlic for 30 seconds. Add zucchini, red pepper and eggplant; cook 7 to 10 minutes, or until crisp-tender. Stir in tomato sauce, oregano, crushed red pepper, if using, and salt and pepper.
Meanwhile, cook ravioli for about 5 minutes. When tender, drain and set aside.
Divide the vegetable mixture into equal-sized portions, and place on serving plates or in large soup bowls. Top with ravioli and sprinkle with shredded cheese. Serve immediately.
By changing the ravioli filling, this dish calls for various wines. Consider pairing it with those based on the varieties Sangiovese, Cinsault, Nebbiolo and Tempranillo.