1 pound boneless skinless chicken breast
1 1/2 cups chicken broth
1 tablespoon fresh dill sprigs, chopped fine
1 tablespoon finely chopped fresh chives
1/2 pound boiling potatoes (about 2 medium)
5 cups water
4 cups corn (cut from about 6 large ears), reserving 3 cobs
1/2 teaspoon ground cumin
1/2 teaspoon cayenne
1/2 to 3/4 cup ice water for thinning soup
In a deep saucepan simmer chicken in broth, covered, turning it once, 10 minutes and remove skillet or pan from heat. Let chicken stand in broth, covered, 20 minutes, or until just cooked through, and cool, uncovered. Chill mixture, covered, at least until cold, about 6 hours, and up to 1 day. Drain chicken and shred into a bowl. Add dill, chives, and salt and pepper to taste and toss to combine well.
Peel potatoes and cut into 1/2-inch pieces. In a 4-quart saucepan simmer water, potatoes, corn, reserved cobs, and cumin, partially covered, until potatoes are very tender, about 15 minutes, and cool. Discard cobs and in a blender purée half of corn mixture in batches until smooth, transferring to a bowl. Stir in remaining corn mixture, cayenne, and salt to taste. Chill soup, covered, at least until cold, about 6 hours, and up to 1 day. Before serving, thin soup with ice water if desired and season with salt and pepper if necessary.
Divide soup among 4 bowls and mound chicken in center. Makes about 9 cups of soup and chicken, serving 4 as a main course.