Mussels with Sausage Sauce

This rich dish is very popular in the coastal villages of Languedoc and I have based my recipe on a version recommended by the Association de Femmes du Bassin de Thau (their equivalent of the Women’s Institute). I have also seen one which claims the recipe’s origins to be the ‘cowboys’ of southern Tuscany. They ask you to tie up each mussel with thread to keep the stuffing in, but that is very fiddly and in any case I think it tastes more succulent when some of it is allowed to escape into