Serves 4

Clean the mussels (do not leave them soaking in water).

Prepare the court-bouillon:
Finely chop the celeriac, carrot, onion, and leek greens. Melt a knob of butter in a large pot and sauté the vegetables until lightly softened.

Add the white wine and bring briefly to a boil. Add the bay leaf and parsley, cook for 1 minute, then pour in the water.

Once boiling, add the mussels, cover, and cook for about 5 minutes, until they have opened.

Strain the mussels through a sieve, collecting the cooking liquid (court-bouillon) in a bowl.

Prepare the soup:
Remove the mussels from their shells and discard the beards. Set aside.

Melt the butter in a pot, add the flour, and cook briefly to form a light roux. Gradually whisk in the court-bouillon to avoid lumps.

Add the chopped leek and bring to a gentle boil for 1 minute. Stir in the cream and curry powder, and bring briefly back to a simmer. Add the saffron and cayenne pepper, then return the mussels to the soup.

To finish:
Whip the cream until stiff, stir through the soup just before serving.

Divide between 4 bowls and finish with chopped parsley.