Sometimes, the issues with cooking mussels are logistical. Is your pan big enough to hold enough of them to feed a hungry table? Is it wide enough so they will cook evenly? And how long will the inevitable steam hang around in the kitchen?
The solution to all those seems to be the oven-steaming method in this recipe. Two kilograms of mussels fit nicely into one large or two smaller roasting pans. With a tight lid of aluminum foil, they steam in about the time it takes for you to crisp the pieces of bacon and saute the ribbons of leeks that will go on top. (Cooking those topping separately, by the way, ensures their proper textures.)
Serve with crusty bread..
2kg debearded mussels
3 medium leeks
6 slices thick-cut bacon
1 1/2 cups dry white wine
3 tablespoons unsalted butter
Pinch sea salt
Handful fresh flat-leaf parsley, for garnish
Preheat the oven to 500 degrees. Soak the mussels in a large bowl of water and ice cubes for 15 minutes. Trim the leeks; cut the white and light-green parts crosswise into thin rounds. Place them in a separate bowl of water and ice cubes.
Meanwhile, cut the bacon into 2cm pieces. Line a plate with a few layers of paper towels.
Look over the mussels and discard any that are cracked or don't close when tapped. Lift them out of the water (do not drain) and transfer to a large roasting pan, spreading them evenly. Pour in the wine, then cover tightly with aluminum foil and roast (middle rack) for about 12 minutes. Discard the soaking water.
Place the bacon pieces in a large skillet; place over medium heat. Cook until crisped. Use a slotted spoon to transfer the pieces to the paper-towel-lined plate, leaving the drippings in the pan.
Lift the leeks from the water, shaking off any excess moisture. Add them to the skillet, stirring to coat in the bacon fat. Cook for 3 to 5 minutes, until softened. Turn off the heat.
Carefully uncover the mussels, lifting a corner of the foil farthest from you so the steam can escape away from you. Discard any that have not opened. Make a clearing and add the butter, then sprinkle the mussels lightly with salt. Toss them until the butter has melted, then divide among wide, shallow bowls. Divide the crisped bacon pieces and leeks among the bowls.
Coarsely chop the parsley and scatter on top of each portion. Serve warm, with a discard bowl for the shells.