This was an experiment from culinary school. Between myself and another student, it was the best we could make it. My wife gets evil looks when she eats the leftovers at work because her co-workers can smell the yumminess!
Heat water to near boiling. Add bouillon cubes and combine completely. If using broth, skip this step. In a small bowl, combine all seasons and spices until completely combined. Add to liquid.
Place chicken in a medium sized sauce pot. Pour the combined liquid/seasonings and spices over the chicken. Cover and heat over low heat. Check every once in a while for doneness.
When chicken is completely done, remove chicken from pot and shred, one at a time, using two forks. Place shredded chicken back into the sauce pot to simmer for two hours, stirring every 30 minutes.
Combine cornstarch and milk into a slurry. Turn the heat up on the chicken mixture until at a low boil. Add the slurry and stir constantly until slightly thickened. (It will still be slightly thin, but that's what you want!)
Preheat oven to 350F.
Spray 9x13 baking dish with non-stick spray. If using flour tortillas, simply layer the beans, chicken and then tomatoes. Use only 3/4 of the can of tomatoes. If using corn tortillas, heat in the microwave between moistened paper towels to prevent them from drying out, then follow the direction for layering for the flour tortillas.
Lay the enchiladas in the baking dish, seam side down, touching each other. After laying them out, pour the remaining sauce over the enchiladas, spreading with spatula to completely cover them. Sprinkle the cheddar cheese then the jack cheese over the center 3/4 of the dish, leaving the edges uncovered. Layer the remaining tomatoes over the center of the cheese, right down the center of the enchiladas.
Baked for 20-25mins or until cheese begins to get a nice golden brown crust. Remove and let cool for 5mins.