Leek Soup

• 1 lb leeks
• 1 onion
• 1½ oz butter

Clean the leeks, leaving as much green as you can, and peel the onion. Chop both as finely as possible, which takes ages. Melt the vegetables in the butter in a large pan for about 15 minutes, stirring often, and without browning. Stir in the flour, allow it to thicken and then add the stock gradually. Season and simmer covered until the leeks are tender but still a pleasant green. Serve with c