Finely chop the onion and half of the fennel and slice the other half. Bring broth to the boil and cook fennel for 3 minutes. Remove thicker slices. Puree the rest into a creamy soup. Let simmer for another 2 minutes. Pour soup into glasses or small bowls. String Appenzeller® cubes and fennel slices on wooden skewers. Garnish soup with fennel greens and caraway and one fennel and cheese skewer per bowl.