Trim, peel, and cut the carrots into 1-inch lengths. Trim, peel, and chop the onion and garlic.
In a heavy pot or Dutch oven, saute the onion in the butter and olive oil over medium heat, stirring, until translucent. Add the garlic and saute it for a few minutes, taking care not to let it brown.
Add the water, carrots, ginger, and salt and cook until the carrots are very tender, about 45 minutes. Turn off the heat and let the soup cool.
When the soup has cooled, puree it in batches in a food processor or blender. Return the puree to the pot and place it over medium-high heat. Bring the puree to a boil and reduce it to the desired thickness. Add the honey, stirring until dissolved. Taste, adjust the seasonings, if necessary, and serve immediately.
To serve cold, remove the pan from the heat and let the soup cool completely. Cover the pot and refrigerate. When ready to serve, stir vigorously and ladle into chilled bowls, if desired
Recipe courtesy MANGIA (HarperCollins, 2001) by Ricardo Diaz and Nancy Jessup