Buzz
Most crabs you find at the grocery store, including whole Dungeness and Alaskan legs, are typically pre-cooked and frozen. This helps extend shelf life and retains the flavor, but it also means preparing crab becomes a straightforward heat-and-serve process. To avoid overcooking while reheating, an immersion circulator is highly recommended.
Steaming or boiling crab is not particularly difficult, but complications can arise if you get distracted or plan to eat multiple crabs. Personally, it takes me about 30 minutes to finish one Dungeness crab, and by the time I'm done, the second one is cold, which is disappointing. The same happens when tackling a pile of legs. With sous-vide, however, the lower temperature of the water bath allows the crabs to cook for up to an hour without risk of overcooking. This way, you can enjoy freshly heated crab whenever you're ready.
A bonus to sous-vide cooking is the liquid in the bag. While most sous-vide recipes benefit from sealing food in a vacuum bag for even cooking and proper submersion, crab's claws and legs are less suited for this due to their shape. Additionally, crab is quite buoyant, so some extra help is needed to keep it submerged. Instead of using weights or butter knives, you can add a cup or two of water to the bag and clip it to the side of the bath. This helps keep the bag submerged while infusing the water with crab flavor—essentially making crab stock, which can be used to create a delicious risotto. You can also add herbs or Old Bay to the bag, but I prefer to cook my crab simply and dip it in butter.
Your preferred type of crab
Water
Drawn butter for dipping
Fill a tub or bucket with water and set the temperature to 140℉. Place your whole crab or crab legs into gallon-sized freezer bags, adding two cups of water to each bag. Submerge the bags in the water bath, clipping the open side over the edge. Let the crab cook for at least 30 minutes, or up to an hour. Once done, remove the crab from the bag, save the flavorful stock for later use, and enjoy with plenty of drawn butter.
