Step 1Heat the butter in the large pot over medium-high heat. Once melted, add the shallots. Cook for 2 minutes until the shallots are soft and just beginning to brown. Add the wine and bring to a boil (cranking up the heat all the way). Season with salt and pepper.
Step 2Dump the mussels into the pot, and slap on the lid. Cook just until all the mussels are open all the way (about 10 minutes, no more). Shake the top, keeping the lid firmly pressed on top, then add the parsley and shake again. (You can toss in an additional knob of softened butter at this point, swirling it into the sauce, for a nice, emulsified, enriching boost.) Pour the whole glorious mess into a serving bowl and serve.