1 lb carrots, peeled and cut into 1/2-inch pieces (2 1/4 cups)
3 cups water
1 3/4 cups (14 fl oz) reduced-sodium fat-free chicken broth
1 cup chopped onion (1 medium)
1 teaspoon salt
1/4 teaspoon ground coriander
1/4 teaspoon ground cumin
1/4 teaspoon paprika
1/8 teaspoon cayenne
2 tablespoons mild honey
2 1/2 tablespoons fresh lemon juice
Garnish: 6 thin lemon slices and 1 tablespoon mild honey for drizzling
Combine all ingredients except 1/2 tablespoon lemon juice in a 3-quart heavy saucepan and bring to a boil over moderate heat, stirring occasionally. Reduce heat and simmer, covered, until carrots are tender, 30 to 40 minutes.
Pur�e soup in 2 batches in a blender (use caution when blending hot liquids) until very smooth, then chill soup quickly, stirring occasionally, in a metal bowl set in a larger bowl of ice and cold water, about 30 minutes.
(Alternatively, cool soup, uncovered, 30 to 40 minutes, then chill, covered, until cold, about 4 hours.)
Stir in remaining 1/2 tablespoon lemon juice and salt to taste. Divide soup among 6 bowls with a ladle. Float a lemon slice on top of each serving, then drizzle with honey and serve.
Cooks' note:
Soup can be made 3 days ahead and kept chilled, covered.
Makes 6 servings.