Take one bunch of carrots and trim the green tops off. Using the smallest carrots as your guide, chop them into roughly equal size pieces.
Steam the carrots over 2 cups of chicken or vegetable broth, covered, for about 10 minutes.
Meanwhile, chop about a 1/2 cup each of onion and celery. Heat 1 tsp of butter and 1 tsp of olive oil over medium heat. Add onions, celery, and salt and pepper to taste. Sautee until tender, about 5 minutes.
Combine the contents of the two pans into one saucepan. Add 2 tsp of ground ginger, and a dash of cayenne pepper. Blend the soup until smooth either by using an immersion blender, or by pouring the soup (carefully!) into a blender. If desired, add a 1/4 cup of cream. If you are not able to get the small chunks out by blending, strain the soup through a sieve.
Pour soup into a container and chill in the refrigerator for about 2 hours.