Slow Cooker Chicken Taco Soup

small onion, chopped

refried black beans

frozen corn

tomato sauce

bottle beer

diced tomatoes with green chilies, undrained

chicken broth

taco seasoning

whole skinless, boneless chicken breasts

shredded Cheddar cheese (optional)

sour cream (optional)

chopped cilantro (optional)

diced avocado (optional)