Do not thaw.
Microwave (1100-watt): Remove tray from box and cut small slit in the center of film. Place frozen tray on a microwave-safe plate in the center of microwave and cook on medium high for 14 minutes or until internal temperature reaches 165°F. Remove tray from microwave and let stand 5 minutes. Carefully remove film, slice and serve.
Oven: Preheat oven to 350°F. Carefully remove film from tray before baking. Place frozen tray of lasagna on a baking sheet in the center of the oven. Bake for 1 hour and 20 minutes or until internal temperature reaches 165°F. Remove tray from oven and let stand 5 minutes. Slice and serve.