Step 1

Place the onion, black beans, corn, tomato sauce, beer, diced tomatoes, and chicken broth in a slow cooker. Add taco seasoning, and stir to blend.

Step 2

Place chicken breasts on top of the mixture, pressing down slightly until just covered by the other ingredients.

Step 3

Set slow cooker for low heat, cover and cook for 5 hours.

Step 4

Remove chicken breasts from the soup and shred. Stir the shredded chicken back into the soup, and continue cooking for 2 hours.

Step 5

Garnish with shredded Cheddar cheese, a dollop of sour cream, cilantro and avocado, if desired.