1. Cook bacon in a large saucepan over medium heat until crisp. Remove bacon with a slotted spoon, reserving 1 teaspoon drippings in pan; set bacon aside. Add onion and celery to pan; cook 5 minutes or until celery is tender. Stir in 3/4 teaspoon cumin, chile powder, and garlic; cook 1 minute. Stir in bacon, pepper, beans, tomatoes, and broth; bring to a boil. Cover, reduce heat, and simmer 10 minutes. Place half of bean mixture in a blender. Remove center piece of blender lid (to allow steam to escape); secure blender lid on blender. Place a clean towel over opening in blender lid (to avoid splatters). Blend until smooth. Pour into a large bowl. Repeat procedure with remaining bean mixture; process until smooth. Keep warm.
2. Combine sour cream, remaining 1/4 teaspoon cumin, cilantro, rind, and juice in a small bowl. Drizzle cream over soup.