Drain and rinse the beans to remove excess salt.
Place half the beans in a blender or food processor with some water and process until blended, but still slightly chunky.
Transfer the puréed beans to a 5 or 6-quart slower cooker, along with the remaining whole beans.
Add chicken, red onion, garlic, green chilies, spices, and chicken broth to the slow cooker.
Season with salt & black pepper.
Stir to combine.
Cover & set cook time to 4 hours on high or 8 hours on low.