Thaw the crab legs in the refrigerator overnight
Rinse the crab legs under cold water
Fill a large pot with 1 to 2 inches of water
Place a steamer basket or rack in the pot
Bring the water to a boil
Add the crab legs to the steamer basket
Cover the pot with a lid
Steam for 5 to 7 minutes until heated through
Remove the crab legs carefully with tongs
Serve with melted butter or lemon if desired