Preheat oven to 350°F. Stir salsa, tomato sauce and cumin together. Spread ½ cup salsa mixture in the bottom of a sprayed 13x9-inch baking dish.
Top with frozen ravioli, beans and corn. Pour remaining salsa mixture over top and sprinkle with cheese. Cover with aluminum foil and bake 45 minutes.
Uncover and bake another 10-20 minutes or until bubbly. Let stand 10 minutes before serving.
Top each serving with a dollop of sour cream, if desired.