Place chicken thighs in slow cooker and top with green pepper and onion. In blender, combine chicken broth, salsa and 1 can of the beans (drained and rinsed). Puree until smooth. Add to slow cooker, along with cumin and black pepper.
Cover and slow cook for 6 hours on HIGH or 8 hours on LOW. Uncover, and remove chicken thighs to cutting board. Stir corn, remaining can of beans (drained and rinsed) and cilantro into slow cooker. Shred chicken and return to slow cooker. Serve with tortilla chips, if desired.