Crab Soup with Cress Mousse, a recipe from the Worldwide Gourmet

Ingredients

• - 200 g (7 oz.) Crab meat
• - 1 tbsp. butter
• - 1 leek, white part only
• - 1 fennel bulb
• - 1 sweet potato
• - Salt and pepper
• - 500 ml (2 cups) light chicken stock
• - 750 ml (3 cups) milk
• - 6 tbsp. sherry