In medium pan, combine chicken, taco
sauce, chicken stock, salt and pepper,
and cook on low, covered, approximately
2 hours, or until internal temperature of
chicken reaches 165 degrees.
Remove chicken from pan and shred using
two forks. Turn heat to medium-high
and reduce cooking liquid into thick
sauce, cooking 3-5 minutes and stirring
occasionally. Remove from heat and
combine sauce with shredded chicken.
Serve in taco shells with desired toppings