Prior to do any of the cooking for this recipe, make sure that you’ve followed the above instructions on how to clean the mussels and discard the dead ones.
In a very large skillet over a medium-high heat, melt the cooking fat and sauté the shallots or onions until translucent and tender, about 3 to 5 minutes.
Add the wine, parsley sprigs, thyme and bay leaf. Turn up the heat and allow the mixture to come to a boil. Reduce the heat and continue to simmer, allowing the wine to reduce. Simmer for 3 to 4 minutes.
Add the mussels and cover the skillet completely. Cook for 4 to 5 minutes, being sure to toss the covered skillet a few times.
After about 4 minutes, all the shells should have opened. Any shells that have not opened at this time are no good and must be discarded. Taste and season with salt and pepper if needed. Remove the bay leaf.
Serve drenched in the white wine sauce and sprinkle with lemon zest and chopped parsley.