SERVES 
The Italian name for this soup is vellutata , which means ‘velvety’, and this soup is indeed quite velvety and delicious. It is a favourite of mine, despite it not being really Italian. The recipe was given to me by a friend, a very good English cook. I like the soup very much because the watercress here is not really cooked, just heated through, and thus it keeps its distinctive peppery flavour.
- Heat the butter and oil in a large saucepan and add the onion together with a pinch of salt. Gently saute the onion for a few minutes, stirring frequently so that it just becomes soft and slightly coloured, not golden.
- Drain and rinse the cannellini beans and add to the soup together with the stock. Bring to the boil.
- Add the watercress and spinach to the saucepan and mix well. Do this a little at a time, all the while stirring so that the vegetables easily fit in the saucepan. As soon as all the vegetables are in, give the soup a good stir and turn the heat off. The watercress and the spinach should just wilt, not cook.
- Use a stick blender to blend the soup for a few seconds. Add salt and pepper to taste and then ladle the soup into individual soup bowls. Serve as it is – and it is very good – or with a jug of pouring cream or, for a delicious kick, with an added pinch of crushed chilli flakes.
