Combine the chicken and water in a large pot over high heat. Cook for 30 minutes to 1 hour, or until chicken is done. Remove chicken from the pot, and cut into bite-size pieces.
Return the meat to the pot. Add the onion, kidney beans, ranch style beans, pinto beans, black beans, hominy, tomatoes, taco seasoning and ranch dressing mix. Mix well, reduce heat to low, and simmer for 30 minutes or until heated through.
