1. Wash and finely chop the leaks

2. Chop the potatoes roughly

3. Melt the 1 oz of butter in a pan and fry the leeks until they are soft but not coloured

4. Add the potatoes and pour over the stock

5. Season with salt and pepper

6. Bring the ingredients to the boil

7. Cover the pan with a lid and let it simmer until the potatoes are tender

8. Remove the pan from the heat and let it slightly cool

9. Put the soup, a little at a time, in a liquidizer

10. Re-heat the puree soup over low heat and stir in the remaining butter

11. Serve immediately

List of ingredients required:

2 leeks
2 pints white stalk
Salt and black pepper
2 lb potatoes
1 and 1/2 oz butter