Wash the mussels under cold, running water and throw away any that don't close when tapped.
Pull out the tough, fibrous beards protruding from between the tightly closed shells and then knock off any barnacles with a large knife.
Give the mussels another quick rinse to remove any little pieces of shell.
Heat a pan, big enough to hold all of the mussels, over a high heat and soften the garlic and shallots in the butter with the bouquet garni,
Add the mussels and wine or cider, turn up the heat, then cover and steam them open in their own juices for 3-4 minutes.
Give the pan a good shake every now and then.
Remove the bouquet garni, add the cream and chopped parsley and remove from the heat.
Spoon into warmed bowls and serve with lots of crusty bread.