Trim, scrape and wash some mussels. Heat 2 tablespoons of butter, add the chopped shallots with 2 tablespoons chopped parsley, the thyme, bay leaf and white wine. Add the mussels, coven the pan and cook over a high heat until all the mussels have opened. Shake the pan several times, if desired.
Remove the pan from the heat and place the mussels into a large serving bowl reserving the cooking liquid. Discard any mussels that do not open. Remove the thyme and bay leaf from the saucepan.
For moules a la marinière, add two tablespoons of butter to the cooking liquid. Whisk the sauce until it thickens and pour it over the mussels. Sprinkle with chopped parsley and black pepper.
For moules a la crème, add the cream and whisk it into the sauce. Sprinkle with chopped parsley and black pepper.