If starting with raw chicken thighs, follow the braising steps below: heat 1–2 tablespoons oil in a large sauté pan over medium-high heat. If using already braised and shredded chicken as listed, skip the searing and braising steps and combine it with the cilantro, jalapeños and filling cheese, then begin warming the tortillas.
Sear the chicken thighs skin-side down until golden brown.
Turn the chicken thighs over and add the salsa roja to the pan almost covering the chicken. If needed add a little chicken stock to bring the sauce level up to almost covering the chicken.
Bring the sauce to a simmer, cover tightly and cook in a 350°F (175°C) oven until the chicken is fork-tender and a food thermometer in the thickest part reads 165°F (74°C), away from the bone. Begin checking after about 50 minutes and continue as needed.
Remove the chicken from the sauce and allow to cool.
Reserve the sauce.
After the chicken is cool enough to handle, shred or pull the chicken meat with a fork and combine with cilantro, jalapeños, and cheese in a bowl and and reserve.
Lightly spray tortillas with cooking spray and warm them in a 300℉ oven to make them pliable for rolling.
Sauce the bottom of a baking dish with some of the salsa roja.
Add 1/2 cup salsa roja to the enchilada filling and stir. Fill the enchiladas with some of the chicken filling and roll, placing the seam-side down in the baking dish.
Repeat with remaining enchiladas.
Add some more sauce to the tops of the enchiladas and then cover with shredded cheddar cheese.
Return the oven to 350°F (175°C). Cover the baking dish with aluminum foil and bake until the center of the enchiladas reaches 165°F (74°C) and the cheese is melted. Begin checking after about 25 minutes and continue as needed.
Uncover and serve immediately, garnished with the listed sour cream, avocado, lettuce and lime wedges.
