Look through the mussels and discard any cracked or chipped mussels otherwise, tiny shells will get into the sauce. If any mussels are open, give them a tap and if they don't close, discard them.
You'll want to remove the beard which is just a clump of hair-like fibers that pop out of the shell. To remove the beard, simply tug it away from the shell using your fingers.
To clean the mussels, use a small brush to scrub the shells then rinse under cold water.
Add olive oil, shallots, red pepper flakes, and garlic to a large pot and cook over medium heat.
Once the garlic becomes fragrant stir in the white wine and cook for 2-3 minutes or until the wine reduces by half.
Add the lobster broth and lemon juice, and cook for 2 minutes. Stir in the butter and season the broth with salt and pepper.
Stir in the mussels, cover with a lid, and give your pot a good shake. Cook for 2 minutes.
Remove the pot from the heat and uncover. If any mussels do not open, simply discard them.
Garnish the mussels with parsley, check for seasoning, and enjoy!