For the clear fennel soup, first roughly dice the onion, carrot and celery. Fry the onion and garlic in olive oil until golden and add to the soup.
Add the fennel to the boiling soup. Remove the fennel from the saucepan after twenty minutes (when it is tender), cut into strips and set aside as a chowder.
Strain the rest of the clear soup and bring to the boil again with the wine, adding saffron threads. Season with salt and pepper. Arrange the fennel in the plates and pour soup over it.
Sprinkle the clear fennel soup with fennel greens and serve.