Bring a large pot of water to a boil. Add ravioli and cook for 5 to 8 minutes or until al dente; drain.
Heat the butter in a skillet over medium heat. Stir in the mushrooms and garlic, and cook until tender.
In a medium saucepan over low heat, toss the cooked ravioli with the Alfredo sauce to coat. Mix in the mushrooms and garlic. Cook and stir until sauce is heated. Top with Parmesan cheese, green onion, and red pepper to serve.