Heat butter and oil in a large heavy-based pan. Add the potatoes,leek,onion,garlic and bay leaves and cook on a low heat,stirring frequently until the leeks have softened.

Add the stock and simmer,covered,for about 25 minutes or until potatoes are very tender. Remove the bay leaves and puree the soup until smooth. Return the soup to the saucepan and stir through the cream. Season to taste. Add more chicken stock if necessary to give the desired consistency.

Ladle into soup bowls,garnish with parsley and,if desired,some of the suggestions below. Serve with crusty bread.

TIPS

• As well as garnishing with parsley you can also serve the soup with some crumbled blue cheese and crispy pancetta,as pictured.

• If you prefer,use some grated aged cheddar,a spoon of creme fraiche or pan-fried speck as garnishes.