1. Cook ravioli according to package directions.
2. Meanwhile, in a small nonstick saucepan coated with cooking spray, saute the mushrooms, onion, nuts and peppers in oil until tender.
3. Combine the cornstarch, broth, half-and-half, salt and pepper until smooth. Gradually stir into the pan. Bring to a boil; cook and stir for 2 minutes or until thickened.
4. Drain ravioli. Stir into sauce; heat through. Sprinkle with cheese if desired. Yield: 2 servings.