Cut bell peppers in half lengthwise; discard seeds and membranes. Place pepper halves, skin sides up, on a foil-lined baking sheet; flatten with hand. Broil 18 minutes or until bell peppers are blackened. Place in a zip-top plastic bag; seal. Let stand 20 minutes. Peel.
Place bell peppers, broth, and next 4 ingredients in a large saucepan. Bring to a boil over high heat; cover, reduce heat, and simmer 13 minutes or until carrot is tender.
Place 1 chipotle chile and half of pepper mixture in a blender; process until smooth. Repeat procedure with remaining chile and pepper mixture. Return pureed mixture to pan; stir in half-and-half and salt. Cook soup over medium heat 5 minutes or until thoroughly heated.
Ladle soup into 4 bowls. Top each serving evenly with sour cream and cilantro.