Add ground beef, onion and taco seasoning to a large skillet. Cook until beef is browned, about 10 minutes.
Put the ground beef mixture into the bottom of your slow cooker. Add black beans, kidney beans, diced tomatoes, corn, green chiles, tomato soup and beef broth. You do not need to drain any of the cans, add the liquids of these cans in too. Mix so all the ingredients are combined.
Cook on low for 7 hours. Add can of refried beans and mix. Cook on low for 1 more hour.
Serve in bowls, with shredded cheese, sour cream and crushed tortilla chips on top. Enjoy!