By Tessa Kiros
You can add any vegetables you like to this, preferably those that are in season. I like to use butter or romaine (cos) lettuce.
Heat the oil in a fairly large soup pot. Gently sauté the spring onions and celery until they have softened but not coloured, then add the zucchini, potatoes, peas and half of the lettuce and watercress.Add