Put chopped onion, cans of beans, ro-tel, corn, chicken broth, and spices in a large stock pot and stir to mix.
Put chicken breasts on top of mixture and make sure they're submerged in liquid.
Boil on stove top until chicken is cooked through, approximately 20 minutes.
Before serving remove the chicken breasts from soup and shred.
Return chicken to pot, stir to combine. If using fresh cilantro, add that in just before serving.
Put chopped onion, cans of beans, ro-tel, corn, chicken broth, and spices in Crockpot and stir to mix.
Put chicken breasts on top of mixture and make sure they're submerged in liquid.
Cook on high 6-7 hours or low 8-9 hours.
Before serving remove the chicken breasts from soup and shred.
Return chicken to Crockpot, stir to combine. If using fresh cilantro, add that in just before serving.
Optional Toppings: