Ingredients:

  Amount  Measure       Ingredient -- Preparation Method
--------  ------------  --------------------------------
   6                    leeks
   1      quart         chicken stock
                        salt
                        black pepper
                        ground nutmeg
     1/2  cup           heavy cream
   1                    egg yolk

Preparation:

Clean and trim leeks, using only the white part. Slice thinly. Bring chicken stock to a boil and simmer leeks for about five minutes, until just tender. Season with salt, pepper, and nutmeg to taste. Beat egg yolk with cream and pour in a thin stream into simmering stock. Stir until blended. Serve at once.