The easiest way to cook a whole lobster is by boiling it in a large pot of salted water for anywhere from 8 to 40 minutes, depending on the size. Lobster can also be parboiled, blanched or steamed.
When boiling lobster, 1.5 to 2 lbs. of lobster needs 3 quarts of water. Salt the water to taste with sea salt and bring the water to a rolling boil. Carefully add the lobster to the water and begin timing. If more than one lobster is in the pot, stir them about halfway through the cooking process.
A 1-lb. lobster should cook for about 8 minutes. A 2-lb. lobster needs about 15 minutes of cooking time, and 5 lbs. of lobster should cook for 35 to 40 minutes.
Once the lobster is finished cooking, remove it from the water and place it on the counter to rest for about 5 minutes. This gives the lobster meat a chance to absorb the liquid trapped under the shell, therefore yielding juicier meat.
Steaming is a gentle cooking method that is best for those who don't want to have to precisely time the cooking process. Blanching or parboiling lobster is perfect when a recipe calls for partially cooked lobster meat.