Heat oil in sauce pan over medium-low heat. Add onion and garlic. Saute until soft, 3-4 min. Slowly add chicken broth, tomato sauce, and chipolte adobo sauce and bring to boil. Add cilantro and remove from heat. Pour into crock pot.
Add drained beans, diced tomatoes, corn, cumin, oregano, and stir. Add chicken breasts. Cover and cook on low for 4-6hrs. (Will take longer if you are like me and throw the chicken breasts in frozen!)
Remove chicken and shred with forks. Add chicken back into soup, adjust salt and cumin to taste (I usually don't even need to add salt).
Serve in bowl and top with fat free sour cream, cheese, scallions, and cilantro to taste!