Scrub the mussels well and remove any barnacles and beards (seaweed strands). Use a stiff brush to scrub the shells, and discard any mussels with broken shells or those that do not close when tapped.

Place the mussels in a basin full of cold water with a handful of flour and leave to soak for 30 minutes.

Drain the mussels and place them in a large, deep saucepan with the remaining ingredients, except the butter and lemon juice. Cover the pan and bring to the boil.

Stir the mussels occasionally while they are cooking to help them cook evenly. Cook about 5-8 minutes, or until the shells open. Discard any mussels that do not open.

Spoon the mussels into individual serving bowls and strain the cooking liquid. Pour the liquid into 4 small bowls and serve with the mussels and a bowl of melted butter mixed with lemon juice for each person. Dip the mussels into the broth and the melted butter to eat. Use a mussel shell to scoop out each mussel, or eat with small forks or spoons.

The beards are strands of seaweed that anchor the mussels to the rocks on which they grow. These must be removed before cooking. They can be pulled off quite easily by hand, or scrubbed off with a stiff brush.

Use the amount of garlic that suits your own taste or leave out the garlic, if desired. Chopped fresh herbs may be added.