Preheat oven to 350 degrees. Remove plastic film. Place tray on baking sheet on center rack of oven. Cover with foil. Cook 40-45 minutes.
Microwave: Pull back one corner to vent. Cook on high 8-12 minutes. Rotate. Continue cooking on 50% power for 10-12 minutes. Let stand 1-2 minutes after cooking before removing from microwave. Carefully remove tray from microwave and remove film.