Mushroom Soup

350 g/12 oz dark mushrooms, trimmed and finely chopped
1 onion, peeled and sliced
300 ml/1/2 pint vegetable stock
25 g/1 oz polyunsaturated margarine
25 g/1 oz plain wholemeal flour
600 ml/1 pint skimmed milk
6 tablespoons medium sherry
salt
freshly ground black pepper
6 tablespoons plain low-fat yogurt
Garnish:
50 g/2 oz button mushrooms, trimmed and
thinly sliced
1 tablespoon chopped parsley

Put the mushrooms and onion in a pan with the stock and bring to the boil, then cover the pan and simmer for 20 minutes.

Sieve the mushroom mixture, or purée in a blender or food processor. Set aside.

Melt the margarine in the saucepan, stir its the flour and cook for 1 minute. Pour on the milk slowly, stirring all the time. Bring to the boil, stirring, then simmer for 3 minutes. Stir in the mushroom puree and sherry, and season to taste with salt and pepper. Bring to the boil again, stir in the yogurt and heat through without boiling.

Ladle the soup into individual bowls. Float the sliced mushrooms on top and sprinkle with the parsley.

SERVES 4