I got the latest issue of Cook's Illustrated in the mail yesterday and saw a recipe for carrot ginger soup. I love carrot soup but haven't found a recipe that I like yet. This one looked appealing since it contained both fresh and crystallized ginger, but was really light - no cream or meat, and only 2 tbsp butter. The secret CI ingredients were the crystallized ginger and a bit of baking soda and vinegar (not at the same time), as well as some carrot juice.
You can watch a short video over at Cook's Illustrated. I was so obsessed that I made it tonight. I mostly followed the recipe, except I used olive oil instead of butter, and, since I am lazy and just have a regular blender and not a juicer, I used some carrot puree in place of juice.
There is also a recipe for croutons, and they suggest serving the soup with the croutons, sour cream and chives, but you don't really need to bother because you will be too busy inhaling the soup to care about the other stuff. You can forget about side dishes too. I'm not kidding. I really like carrots, and I really like ginger, and this soup is just about perfect for me. In fact, it is the best carrot soup I've ever had. The lack of milk, cream, or broth really helped the soup, because the flavor is pure carrots and ginger. For this reason, I'm going to suggest that you use olive or vegetable oil instead of the butter. I used sweet onions and that worked well. If you use a carrot puree and don't strain it, you soup will be slightly less smooth.
The baking soda helps soften the carrots so you don't have to cook them as long. They didn't discuss the vinegar but I assume it is to neutralize the baking soda once the carrots are done. The carrot juice serves to give it a fresher flavor than you;d get from broth or just plain water.
OMFG!!- Awesome Healthy Carrot Ginger Soup
2 tbsp olive oil
2 onions (preferably sweet onions), diced
1/4 cup crystallized ginger, chopped
1 tbsp minced fresh ginger
2 cloves garlic, chopped
salt and pepper
1 tsp sugar
2 lbs carrots, peeled and sliced into 1/4" slices
1 1/2 cups carrot juice (I just used a puree and didn't strain it)
4 cups water
2 sprigs fresh thyme
1/2 tsp baking soda
1 tbsp cider vinegar
Combine olive oil, onions, garlic, gingers, 2 tsp salt, and sugar in large soup pot and cook over medium heat, stirring often, until onions are softened but not brown (5-7 minutes). Add water, carrots, 3/4 cup carrot juice, thyme, and baking soda. Increase heat to high and bring soup to a simmer. Cover and reduce heat. Cook until carrots are tender but not overdone (20-25 minutes).
Remove thyme sprigs. Working in small batches, puree soup in blender until very smooth. Return pureed soup to pot and add remaining carrot juice and vinegar. Bring to a simmer. Add salt and pepper to taste.