1 Soak the steamers in sea water or salty water: Ideally, if you have the time, place the steamers in a bucket and cover with several inches of sea water or salty water (a tablespoon of sea salt completely dissolved in every quart of water), and let sit several hours in a cool place (not in direct sunlight), preferably overnight.
After a while, you’ll notice that each clam has a foot that will start to extend out of the shell. This is normal. The clams are usually buried in the sand with only the foot extending up to the surface of the water.
The steamer clams will discharge any sand or dirt while they are sitting in the water, so the water may become rather murky. You can change the water if you want.
If you don’t have time to let the clams soak for hours, just put several of them at a time in a large bowl, cover with salt water, and gently swirl the water around with your fingers for half a minute.
If the clams release sand or grit, dump out the water and rinse the clams out in the same manner again, until no more sand is released. (They may still release some sand and grit while cooking, but you will dip them in the clam broth before dipping them in butter when you eat them, helping to rinse away any remaining grit.)
2 Steam the clams: When ready to cook, put about an inch of water (you can also use beer or a stout) in the bottom of a tall, large pot. Place a steamer rack at the bottom of the pot. Carefully place the clams on the steamer rack (if you don’t have a steamer rack, don’t worry about it, just put the clams in the pot with the water).
The clam shells are on the thin side and can easily break, so be gentle as you put the steamers in the pot.
You may notice some of the clams “spitting” water at you as you handle them. This is normal, don’t worry about it. If any of the clams seem dead, are stinky, or whose siphons don’t retract a bit when you touch them, toss them out.
Cover the pot. Bring the water to a boil. Let the clams cook in the steam from the boiling water for about 5-10 minutes, until the steamer clam shells are wide open, then remove the pot from the heat. Any steamers that didn’t open should be discarded. (The pot might foam up and boil over while cooking, so keep an eye on it while cooking.) Let the clams cool for a couple minutes.
3 Place steamer water in bowls for serving: Carefully remove the cooked clams from the pot, placing them in a serving bowl. Do not discard the clam broth left in the pot. Instead pour a bit of the hot broth into bowls for serving. Put the melted butter into small bowls for dipping.
4 Serve with melted butter: Serve the steamers with a bowl for the clams, an empty bowl for the shells, a small bowl with broth for dipping, and a smaller bowl with butter for dipping.
5 Here’s how to eat the steamers: To eat, open the shell and remove the cooked clam. Use your fingers to pull off the skin covering the siphon of the clam. Discard with the shells into the shell bowl.
Grip the siphon with your fingers, swirl the clam around in the hot broth (it will help to warm up the clams and to dislodge any remaining grit or sand). Dip the clam into melted butter and eat!
Note, the siphon end of the clam may be a bit tough and rubbery. You can eat it or not. In any case, it makes a great handle for dipping.