Remove the core of the fennel and its hard stems. Save the green leaves for garnishing. Cut the fennel in chunks. Peel and cut the potatoes in small cubes.
Heat 2 tbsp of olive in a large saucepan. Add chopped fennel and cook it while continuously mixing until it gets small brown spots. Add potatoes and pour enough water to just cover the vegetables. Throw in a chicken or vegetable cube and bring it to boil. Then let the soup simmer for 10 minutes or until the potatoes are cooked.
Blend the soup using a hand blender until smooth. Distribute into individual bowls, add some olive oil or cream, and the green leaves of the fennel for decoration. Serve with fresh bread.