1 cup dry white wine (like Sauvignon Blanc or Pinot Grigio)
1 loaf crusty bread, for serving
1/2 cup (1 stick) unsalted butter
6-8 cloves garlic, thinly sliced or roughly minced
1/2 lemon, juiced
1/4 teaspoon red pepper flakes
1/2 cup fresh parsley, roughly chopped
1/3 cup grated Parmesan cheese, plus more for serving
Salt and black pepper, to taste
Instructions
Clean the mussels: Place mussels in a colander under cold running water. Scrub each shell with a stiff brush. Pull off any 'beards' (stringy bits) by tugging them towards the hinge of the shell. Discard any mussels with broken shells or any that are open and don't close when tapped.
Start the sauce: Melt butter in a large pot or Dutch oven over medium heat. Add the garlic and red pepper flakes and cook until fragrant, about 1-2 minutes. Do not let the garlic brown.
Deglaze: Pour in the white wine and lemon juice. Bring to a simmer and cook for 2-3 minutes to let the flavors combine.
Steam the mussels: Add the cleaned mussels to the pot, stir to coat, and immediately cover with a tight-fitting lid. Increase heat to medium-high.
Cook until open: Let the mussels steam for 5-7 minutes, shaking the pot once or twice, until most of the shells have opened.
Finish and serve: Turn off the heat. Discard any mussels that remained closed. Stir in the fresh parsley and Parmesan cheese. Season with salt and pepper to taste. Serve immediately in large bowls with all the broth and plenty of crusty bread.
Notes
The most important step is cleaning the mussels well. A little grit can ruin the entire pot, so take your time with the scrubbing and debearding.