Jerusalem artichoke soup with truffle

Method

1. Melt 25g of the butter in a pan and lightly fry the onions until soft. Add the artichokes, stock, water and bouquet garni. You may need to add more water to cover. Bring to the boil and simmer for 20 minutes or until the artichokes are soft.

2. Remove the bouquet garni, then tip the soup into a liquidiser and blend. Pour the soup back into the pan and heat gently until piping hot.

3. Take the soup off the heat, add the remaining butter and blend the soup until you get a cappuccino effect on top. Season if needed.

4. To serve: cook the diced artichoke in boiling salted water for 2 minutes. Drain and divide between four soup bowls. Ladle the soup over the diced artichoke, then drizzle with white truffle oil and garnish with chopped chives and shaved white truffle.