Heat a large soup pot to medium heat and stir in onion, garlic, cumin, oregano, chili powder and pepper until spices are fragrant, about 1 minute.
Add broth, tomatoes and green chilies. Cover and bring to a boil over high heat.
Meanwhile, stack tortillas and cut in to 1/8 inch strips. add to boiling broth. Reduce heat, cover and simmer for 15 minutes, stirring occasionally.
Rinse chicken and cut into 1/2 inch pieces. Add chicken and beans to broth and return to a boil over high heat. Reduce heat, cover and simmer until chicken is cooked through, about 5 minutes.
Stir in cilantro and add lime and salt to taste.
Ladle into soup bowls, garnish with fresh avocado, additional lime and cilantro. Add your favorite hot sauce for an extra kick!