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To steam a lobster, you will need tongs, a plate, fresh water, a large pot with a tight-fitting lid, and a steaming rack. If you don't have a steaming rack, use a metal cooling rack or an upside down colander.  To cook more or larger lobsters, you may have to adjust the cooking time, and you may need a larger pot, more water, and an extra tablespoon of salt. You'll need enough fresh water to fill the bottom of the pot, so the size and shape of the pot will determine the amount of water. To cook up to eight pounds (3.6 kg) of lobster at once, use a five-gallon (19 L) pot. Place the steaming rack in the bottom of the pot and fill the bottom with two inches (5 cm) of water. Add the salt to the water. There are a number of salts you can use for this, including:  Sea salt Kosher salt Table Salt Place the pot onto the largest element you have, put on the lid, and heat it over high heat. As the water comes to a boil, prepare the lobster:  Rinse the lobster under cold, running water and place it on a plate, tray, or other flat surface until the water boils. When the water boils, grab the lobster where the head meets the body. Hold the lobster down and carefully remove the rubber bands on the claws by slipping them off or cutting them with scissors. Watch your hands, or you might get pinched. You can leave the bands on during the cooking process if you're worried about getting pinched. The bands may transfer a bit of a rubbery taste to the claw meat. Immediately after removing the bands, remove the lid from the pot and use your hands or tongs to plunge the lobster head-first into the boiling water. If you're cooking more than one, place them in the pot one at a time. Return the lid and bring the water back to a boil. Avoid crowding the pot if you're cooking more than one lobster. If you can't see the bottom of the pot or can't get the lid on properly, you either need a second pot, a larger pot, or you have to cook the lobsters in two batches. As soon as the lobster goes into the water, start your cooking timer or make a note of the time, because the cooking time is based on when the lobster goes into the pot, not when the water returns to a boil. Cooking times for steamed lobsters are:  10 minutes for one pound 12 minutes for 1¼ pounds 14 minutes for 1½ pounds 16 minutes for 1¾ pounds 18 minutes for two pounds 22 minutes for 2½ pounds 20 to 25 minutes for three pounds 40 to 45 minutes for five pounds 50 to 60 minutes for six to seven pound Halfway through the steaming time, take the lid off the pot. Use the tongs to rearrange the lobster in the pot to ensure even cooking.  Return the lid when you're finished and allow the lobster to continue cooking. When you remove the lid, open it away from you first so the steam escapes on the other side and doesn't burn you. Take the pot off the heat, remove the lid, and use the tongs to remove the lobster from the pot. If you're cooking more than one lobster, remove them one at a time. Place the lobster on a baking sheet until it's cool enough to touch.  To stop the cooking process immediately and speed up the cooling, quickly dunk the lobster in and out of a pot of ice water before placing it on the baking sheet. You can tell that lobster is done when the shell goes bright red, the meat goes white, and an antenna comes out with no resistance when it's pulled.

Summary:
Gather your supplies. Get the pot ready. Heat the water and prepare the lobster. Cook the lobster. Start the timer. Shift the lobster around at the halfway point. Remove the lobsters when they're cooked.