bring chicken to boil in large pot, continue boiling on medium for about 20 minutes.
while chicken is boiling mix all other ingredients in sauce pan bring to a boil stirring constantly than turn down heat and simmer for 5 minutes.
remove chicken from pot and allow to cool. Remove skin from chicken and take out bones. put chicken meat and 1/4 cup of chicken broth reserved back in pot. bring to a boil then turn to low and add bbq sauce mixture coat chicken thoroughly with sauce then serve hot on hamburger buns.