In a small bowl, stir together all of the spices.
Add the chicken breasts to the slow cooker and then sprinkle with the seasoning mix.
Pour the tomato sauce and chicken stock in with the chicken and spices. Mix the ingredients by flipping the chicken breasts a few times.
Cover and cook for 5-6 hours on low.
Remove chicken from the slow cooker and place it into a glass mixing bowl. Using a hand mixer or two forks, shred the chicken. You can shred the chicken in the crockpot, but I like to control the amount of sauce in with the chicken, so I shred it separately in a bowl.
Add 1/2 of a cup or so of the sauce from the slow cooker in with the chicken. Then squeeze in some lime juice and season with extra salt and pepper.