9 (1-cup) servings.
Cook bacon in a Dutch oven over medium heat until crisp; remove bacon, and set aside, reserving drippings in pan. Saute onion, carrot, celery, and garlic in drippings 3 minutes or until tender.
Position knife blade in food processor bowl; add bacon and vegetable mixture. Process 1 1/2 minutes or until smooth. Wipe pan with a paper towel; add bacon mixture, 2 cans black beans, chicken broth, and next 8 ingredients.
Place remaining 1 can black beans in a bowl; mash with a fork, and add to soup mixture. Bring to a boil; reduce heat, and simmer, uncovered, 30 minutes or until thickened. Ladle soup into individual bowls. Top each serving with 1 tablespoon sour cream. Garnish with fresh cilantro leaves, if desired.