In a crockpot, combine the tomato sauce, chicken broth, chipotle in adobo sauce, chili powder, paprika, cumin, onion powder, garlic powder, and salt. Mix everything together until well combined.
Add the boneless, skinless chicken breasts to the crockpot, ensuring they are covered with the sauce. Cover the crockpot with its lid.
Cook the chicken on high for 4 hours until it becomes tender and easily shreds with a fork.
Once the chicken is cooked, remove it from the crockpot and place it in a bowl. Use two forks to shred the chicken into small pieces.
Take 1/2 cup of the sauce from the crockpot and mix it with the shredded chicken to keep it moist and flavorful.
Preheat your oven to 400°F (200°C).
Pour enough sauce from the crockpot to cover the bottom of a 9 x 11-inch glass baking dish.
Lay one tortilla on a plate, spoon some of the shredded chicken mixture onto the tortilla, and roll it up. Place the filled tortilla seam-side down into the baking dish. Repeat this process for all 12 tortillas.
Once all the tortillas are in the baking dish, pour the remaining sauce over the top, ensuring they are well coated.
Sprinkle the shredded cheddar cheese evenly over the top of the enchiladas.
Bake the enchiladas in the preheated oven for 15-20 minutes or until the cheese is melted and bubbly, and the enchiladas are heated through.
To serve immediately, top the enchiladas with shredded lettuce, low-fat Greek yogurt or sour cream, and salsa according to your taste preferences.
For meal prep, let the enchiladas cool down a bit after baking, then divide them into meal prep containers, placing two enchiladas in each container. Refrigerate the meal prep containers for later consumption.