The day before, soak the lentils in cold water – preferably for one night. One day later, fillet and skin the smoked eel, setting the skin aside. Peel the shallots and the garlic clove and cut them into fine cubes. Clean and peel the carrots and celery and cut into small cubes. Drain the lentils in a sieve.
Heat the butter in a saucepan and roast the smoked eel skin in it at low temperature. Add the lentils with the bay leaf spice and the thyme sprigs. Pour the clear soup and let it boil.
Cook the lentils al dente over medium heat for about half an hour.
Remove the eel skin, bay spice and thyme sprigs. Add the diced vegetables and continue cooking for 10 minutes. For the chowder, remove 4 tbsp of lentil vegetables and place in a small saucepan. Cook the rest of the lentil vegetables until soft and blend finely with a hand blender.
Strain the pureed lentil soup through a sieve and season with fleur de sel and freshly ground pepper. Reheat the soup and the chowder, mix the parsley into the chowder. Cut the smoked eel into pieces of about 3 cm. Mix the lentil soup with the whipped cream and distribute evenly on preheated deep plates. Serve the eel pieces and the lentil vegetables separately in dessert bowls.