Place everything but the shells and toppings in the slow cooker. Stir the ingredients a little to combine.
Set the slow cooker to the low setting and cook for about 5 hours.
Remove the chicken from the slow cooker and place on a cutting board. Shred the chicken.
Cook the taco shells according to the package directions.
Put the meat and toppings into the taco shells.
Recipe adapted from Chef In Training