Cream Of Leek And Potato Soup Recipe

1 Wash the leeks well (this is best done by standing them, green stems down, in a jug of cold water so grit and dirt can float out from between the stems). Drain them and cut into thin slices. Peel the potatoes and cut into quarters.
2 In a pan, melt the butter. When hot add the leek slices. Soften them a little in the covered pan, stirring frequently over gentle heat.
3 Take the pan off the heat and pour in the stock. Return to the heat and bring to a boil again. Add salt and pepper. Put in the potato quarters, cover the pan, reduce the heat and simmer about 20 minutes till tender. Then puree in a blender or work through a strainer or food mill.
4 In a bowl blend the cream and egg yolk together, then stir in some of the hot soup. Return this mixture to the soup. Stir and adjust the seasoning, adding plenty of pepper. Heat gently for a few moments but do not boil.
5 Meanwhile, wash and dry the chervil or parsley, then chop it finely.
6 Pour the soup into a heated tureen. Sprinkle with the chopped herbs and serve