In a large skillet, cook turkey over medium heat until no longer pink; drain. Sprinkle with garlic powder, salt and pepper; set aside.
In a large saucepan, cook carrots and mushrooms in oil until tender. Stir in spaghetti sauce. Spread 1/2 cup sauce in a greased 13-in. x 9-in. baking dish. Layer with half of the ravioli, spaghetti sauce mixture, turkey and cheeses. Repeat layers. Sprinkle with parsley if desired.
Cover and bake at 375° for 25-30 minutes or until bubbly. Uncover; bake 10 minutes longer. Let stand 15 minutes before serving. Yield: 12 servings.