Sauté shallots in butter until soft, deglaze with white wine, beef broth and the snail stock. Add saffron, garlic and thyme leaves and reduce the liquid to just over half.
Add vegetables and snails, make twenty minutes on low heat.
Thicken the ragout with a little flour butter and crem fraiche and season with a few drops of Pernod.
Serve with white bread or puff pastry fleurons.