Preheat oven to 350°. In a Dutch oven, cook the beef, onion, mushrooms and garlic over medium heat until meat is no longer pink, crumble beef; drain. Stir in the tomato sauce, tomato paste, pepper and 2 cups mozzarella cheese; set aside., In a large bowl, combine the Alfredo sauce, ricotta cheese, peas and spinach., Spread 1 cup meat sauce into a greased 13x9-in. baking dish. Layer with 4 noodles, 1-1/4 cups meat sauce and 1-1/4 cups spinach mixture. Repeat layers 3 times. Sprinkle with remaining 2 cups mozzarella cheese. (Pan will be full.), Cover and bake for 45 minutes. Uncover; bake 10 minutes longer or until cheese is melted. Let stand for 10 minutes before cutting. Garnish with basil and, if desired, serve with Parmesan cheese.