Put half the butter, shallots, garlic and bouquet garni into a heavy bottomed pan with a tight-fitting lid. Cook on a high heat taking care not to colour the shallots.
Just before the shallots start to colour add your mussels and white wine and fit the lid giving the whole thing a little shake.
Once it has come back to the boil give them another shake, they should take about another 5mins cooking or until the mussels are open and plump.
Scoop out the mussels with a slotted spoon serving straight into pasta bowls, discarding the bouquet garni and any mussels that aren’t open or are broken.
Pour the liquid gently into another clean pan leaving a bit of the cooking liquid behind to leave behind and grit from the mussels.
Bring the liquid in the new pan up to the boil whisk in the remaining butter and parsley and split evenly between your two dishes.
Tip: Before cooking, use the back of a small knife to knock the barnacles off and grab the beards between your thumb and the knife to pull them off. The more dedicated of you can scrub them with a metal scourer. If the mussels don’t shut after tapping, discard them as well as ones with broken shells.