Add chicken to the bottom of a slow cooker. Season with salt, pepper, cumin, oregano, and cayenne pepper. Top with onion, garlic, and chilis. If using dry beans, add them in this step.
Add chicken broth, avoiding pouring directly on top of the chicken. Cook on low for 7-8 hours or until chicken pulls apart easily with a fork.
Remove chicken and shred with two forks. Set aside.
In a small bowl, whisk coconut milk and arrowroot flour. Whisk into soup broth, then add chicken and beans (if using canned variety) into slow cooker and mix.
Re-cover and cook an additional 30 minutes on high.
Serve with desired toppings.