Prior to the mid 1950s, this was commonly known as Creamy Potato Soup (except in France, of course!), but the Baby Boomers went crazy for this indulgent-sounding dinner party course and recipes abound in cookery books and entertaining guides until the mid 80s.
- Cut leeks into 5mm (1/4 inch) slices, use white parts plus about 1 inch of the lightest green leek. Chop onion finely, melt butter in a large heavy saucepan and saute leeks and onion, covered, over moderate heat until soft (about 10 minutes). Avoid burning.
- Add chicken stock, sliced potatoes. parsley, celery stalk, salt and pepper. Simmer until potato is tender (about 30 minutes). Cool. Rub through a sieve or puree in an electric blender. Reheat until just short of boiling point. Taste and adjust seasoning if necessary.
- Just before serving, stir in the very cold cream. Serve at the table from a chilled tureen, sprinkle a scant teaspoon of the chives on top of each helping.