Lettuce Soup

1 large onion, finely chopped
2 tablespoons butter
1 lettuce, shredded
1 litre chicken stock (homemade for preference)
2 tablespoons lemon juice
grated lemon rind
light sour cream or yoghurt

Melt the butter in a large pan and saute the onions until tender. Add the lettuce, sweating it for a couple of minutes, before adding the chicken stock. Simmer for 10 minutes. Puree in a blender then add the lemon juice and rind and reheat. Just before serving, stir in around a quarter of a cup of light sour cream or yoghurt. Don't let the soup boil after this stage. Lettuce soup can also be served chilled. Some of those outer lettuce leaves you usually discard when making salad can be used in lettuce soup. For garnish a few shreds of lettuce - red lettuce is attractive - parsley, snipped chives or alfalfa sprouts are options.