Recipe from Plaisirs Napoléoniens.
Vine snails in chicken fricassee [but without chicken]
To get them out of their shells and clean them well, you put a good handful of ash [NB: to wash at best] in a cauldron with river water [NB: considered cleaner for consumption than well water, too stagnant]; when it starts to boil, put the snails in it [NB: there is no question of making them bleed from their slime] and leave them for twenty minutes at most; when they easily get out of their shells, clean them and put them again in a new one you let them boil for a moment; drain them and put-bake them in a saucepan with a piece of butter, a bunch of parsley, chives, thyme, bay leaf and mushrooms; add a pinch of flour, wet with broth, a glass of white wine, salt, pepper; cook until the snails are soft, and that there is a little sauce left; while serving, put a three-yolk bond in it with cream; make it bind without boiling; add a bit of verjuice or white vinegar, with a bit of nutmeg