2 tablespoons olive oil
2 medium onions, sliced
2 medium carrots, cut into 1/4-inch-thick slices
1 tablespoon finely chopped peeled fresh ginger root
3 cups water
1-3/4 cups nonfat chicken broth
2 cups canned pumpkin
1/2 cup light sour cream
Heat olive oil in a stockpot over medium heat until hot, but not smoking. Add onions, carrots, and ginger; cook until golden, stirring constantly. Stir in the water, chicken broth, pumpkin, and nutmeg. Reduce heat and simmer for about 5 minutes, stirring occasionally. Remove from heat.
Puree soup in a blender, carefully working with small batches at a time. Do not fill blender more than half way each time. Pour pureed soup into a soup tureen or back into stock pot. Season with salt and pepper if desired. Serve each bowl of soup with a dollop of sour cream, and sprinkle with additional nutmeg to garnish.