(Photo from North 45 Pub.)
Last night, Boyfriend and I steamed a bucket of mussels for dinner and ate them with a loaf of semolina bread and a simple green salad. When we lived in England, we used to go to a small chain of Belgian-style restaurant called Belgo, for both its extensive Belgian beer list and the moules frites.
For about £12(GBP), we'd get a kilo of mussels (about 2.2lbs.) and a bowl of golden fries. There are limitless broths to make for steaming mussels, but the classic Belgian method is to use white wine, celery, garlic, onions or shallot, and a touch of cream. In English menus, you'll always find at least one option for some kind of Thai curry with cilantro (or "fresh coriander") and coconut milk. Another way I like them is with finely diced pancetta (or lardons, or smoked ham), onions, celery, light beer, and a lot of fresh parsley.
Cooking mussels at home intimidates some people, I think, because when you get sick from mussels, you get really, horribly, disgustingly ill. However, if you make them at home, there's so little chance of getting sick. Most people who get sick from mussels ate ones that were stored improperly. The trick is to keep them fully submerged in ice water, or on ice, and to change the water frequently. They can't be left in their own filth for long, so when mussels are left in the same water for a full day or overnight, as might happen in a busy restaurant, they essentially get sick or die, and eating dead or sick mussels is a recipe for disaster.
Another thing that turns people off is getting one single grain of sand in their food. There's a trick to making sure that doesn't happen. When you get a live batch of mussels home, put them in very cold water, and sprinkle a teaspoon or two of ordinary flour into the water. It will dissolve; the mussels will eat it; but then they'll realize they don't like it and spit it out. After they've been submerged for an hour or so, move them to completely for fresh ice water, and they'll continue to disgorge all the sand, flour, and whatever else they have in them, leaving you with sand-free moules.
Most importantly, always eat mussels the same day that you purchase them.
How to Cook Mussels
Coat the bottom of a very deep metal pot with cooking spray or a few drops of oil and set it over low heat. Except for the mussels and parsley, toss in the all the solid ingredients—ham, onions, shallots, garlic, celery—and cook until softened. Add enough white wine, beer, vegetable broth, or whatever main liquid you're using, to just cover the bottom of the pot and turn up the heat to medium. Bear in mind that the mussels will give off a lot of liquid, so you don't need much to start—just enough to give flavor.
Drain the mussels from their ice water, and gently tumble them into the pot. Cover and allow to simmer, just below a full boil, for about five minutes. Give the pot a good shake with the lid on, then check to see if the mussels have opened. If there are more than one or two that have not opened, continue cooking for another three minutes. It's hard to overcook mussels, so don't be afraid to let them go for up to 12 minutes. After that time, if any have not opened, do not eat them! Finally, while the pot is still warm, sprinkle on top the chopped parsley, cilantro, or other fresh herbs, and cream if using. Toss to combine.
Serve with fries or crusty bread and an empty bowl for collecting the shells.