In the Refrigerator
After thawing in the refrigerator, use previously frozen lamb roasts and chops in 3 to 5 days and ground lamb and stew meat in 1 to 2 days. Meat defrosted in the refrigerator may be refrozen before or after cooking. However, there may be a loss of quality due to the moisture loss.
In Cold Water
Leave frozen lamb in its packaging, making sure it is airtight; transfer it to a leak-proof bag if you’re uncertain. Submerge the package in cold water, changing the water every 30 minutes until the lamb has thawed completely. Lamb that is thawed to room temperature should not be refrozen without cooking first.
In the Microwave
As with the cold water method, cook lamb thawed in the microwave immediately and do not refreeze before cooking first.