How to Reheat Frozen Lasagna

Reheating lasagna from frozen takes some time, so be sure to plan ahead.

For the best results and quickest reheating, thaw the frozen lasagna in the refrigerator overnight.

For quicker reheating from frozen, thaw lasagna in the microwave first and then finish it in the oven.

Oven Method

Preheat your oven to 400 degrees Fahrenheit. Cover the lasagna in aluminum foil and place it in the oven on a middle shelf.

Heat the lasagna in the oven until the fillings begin to sizzle. Take the internal temperature of the lasagna; it should register at 165 F using a kitchen thermometer when it is fully heated. This may take upwards of 1 hour to complete, depending on the number of layers included and how large a lasagna you are reheating.

Take the foil cover off of the lasagna and continue cooking it for about 10 more minutes, until the top is well browned. Remove the lasagna from the oven and allow it to rest for 5 to 10 minutes before serving.

Microwave Reheating

Place the lasagna on a microwave-safe plate or tray. Cover with wax paper or microwave-safe plastic wrap to prevent splattering.

Use the defrost setting on your microwave to thaw the cooked lasagna. Depending on the size, this will take anywhere from a couple minutes for a personal portion of frozen lasagna to upwards of 10 minutes for a tray of lasagna.

Set your microwave to heat the lasagna at full power once it is thawed; use 2 or 3 minutes on high for a single portion of lasagna and 5 to 10 minutes for larger portions. Use a kitchen thermometer to ensure that the internal temperature reaches 165 F.

Take caution when removing a hot tray of lasagna from the oven and when taking off its cover, as the steam coming from it can be dangerously hot. 

Instructions from Live Strong.