chicken taco soup

i made this dish last week and failed at getting a picture of it. we love this recipe and eat it multiple times throughout the fall and winter months.

1 white onion, chopped finely
1 (16 oz.) can chili beans
1 (15 oz.) can black beans, drained and rinsed
1 (15 oz.) can whole kernel corn, drained
1 (8 oz.) can tomato sauce
2 (10 oz.) cans diced tomatoes with green chiles
1 (1.25 oz.) package taco seasoning
3 whole skinless, boneless, chicken breasts, thawed or frozen
stir onion, beans, corn, tomato sauce, dice tomatoes, and taco sauce into a slow cooker. *i sautee the onion before to make sure that they are not crunchy. lay the chicken breast on top of the mixture, pressing down slightly so that it gets covered by other ingredients. set slow cooker to low heat, cover, and cook for 3-4 hours on low if your chicken is thawed. may take 4-5 hours on low if your chicken is frozen. ( i usually cook mine with frozen chicken for 8 hours or more because i am at work)
remove chicken breasts from the soup and shred. stir shredded chicken back into the soup. your technically supposed to cook it on low for another 2 hours in the crockpot but you really don't have to. i never do. it's very forgiving. you can leave it in longer if you want too.