Coat a medium saucepan with cooking spray, and place over medium-high heat until hot. Add onion, bell pepper, and garlic; sauté 3 minutes. Add chili powder and next 8 ingredients (chili powder through broth); bring to a boil. Stir in half of beans; cover, reduce heat, and simmer 10 minutes.
Place soup in a food processor or blender, and process until smooth. Return to pan; stir in remaining beans. Cook until thoroughly heated.