2 lb | 900g cooking tomatoes
3 pints | 1700ml stock or water
a few celery seeds (tied in a muslin bag) or a piece of celery when in season
1 oz | 28g margarine or butter
pepper and salt
cornflour about 1 tbsp
1 or 2 carrots, peeled and sliced
2 onions, peeled and sliced
cornflour

Melt the margarine or butter in a saucepan, add the prepared vegetables and cook them for a few minutes without letting them brown.

Remove the saucepan from the fire and add the tomatoes, stock or water, seasoning and celery. Simmer all together until tender, then strain through a fine sieve.

Return the puree to the saucepan, stir in a little cornflour mixed to a smooth paste with water. Boil for a few minutes, season to taste and serve with fried croutons.