Wash the mussels very well and discard any that are open and won't close with a bit of gentle finger pressure.
Pour the liquid and other aromatic ingredients of your choice into a large pot with a tight fitting lid. Stir to combine and bring to a simmer over medium-high heat. Add the mussels and cover with the lid. Shake the pot occasionally and cook until all the mussels have opened, 10 minutes or so.
Spoon out the mussels into a serving bowl. Strain the remaining liquid to remove any broken shell or lingering sand in it. Serve with the mussels and lots of bread for soaking up the flavourful juice!