Note: you can make tomatillo sauce ahead of time and store in the glass jar with a lid (or another food storage container) in the refrigerator. You can make the sauce up to 2 days ahead of time.
Tomatillo Sauce:
Preheat oven to 425° and line a large baking sheet with aluminum foil. Lightly grease the foil with some cooking spray.
Remove the husks and wash the tomatillos. Cut tomatillos and jalapenos in half and cut onion in fourths. (You can discard jalapeno seeds if you want your sauce to less spicy.)
Place tomatillos, onion, and jalapenos on the baking sheet, cut side up, and bake for 20-30 minutes depending on the size. Add garlic cloves about half way through the baking.
Once roasted, add everything (including the juices) into a food processor. Add in cilantro, lime juice, salt, chili powder, as well. Pulse until everything is well blended.
Chicken filling:
Preheat the oven to 425° and lightly grease a 9x13 baking dish.
Spread some tomatillo sauce over the bottom and place chicken thighs over the sauce. Season with some salt and add a little more sauce on top.
Bake chicken for 18-23 minutes, until completely done.
Take chicken out of the baking dish and shred it using two forks.
Mix in a couple tablespoons of tomatillo sauce into the shredded chicken.
Prepare Enchiladas:
Preheat oven to 350° and lightly grease a 9x13 baking dish. Spread half of the tomatillo sauce in the bottom of the baking dish.
Grate the cheeses on a large box grater.
Divide Pepper Jack cheese among 8 tortillas and then divide shredded chicken among the 8 tortillas.
Roll them up and place them seam down in the baking dish.
Spread remaining tomatillo sauce over the rolled enchiladas and top them all off with Monterrey Jack cheese.
Bake for 15-20 minutes, until hot throughout and cheese is all melted.
Top enchiladas off with your desired toppings and serve!
Video
Notes
Flour vs Corn Tortillas: this is a personal taste preference! Flour tortillas are softer and sturdier, white corn tortillas do have a tendency to break and crumble. There is also a noticeable flavor and texture difference between the two types of tortillas, that is mostly where personal preference comes in. You can absolutely use corn tortillas if that is what you love or use flour.
If you want to use corn tortillas for enchiladas, it is important to soften them! Trying to roll cold tortillas will be frustrating because they will be breaking.To soften corn tortillas, lightly brush or spray them with some oil and place them on a sheet tray. Bake at 325° for 3-5 minutes. After they’re warmed, stack them and cover with a damp warm clean towel to keep them soft while rolling enchiladas.
Make Ahead Suggestions: enchiladas verdes are easy to prep ahead of time. You can always make the tomatillo sauce a day or two before and keep in in the refrigerator, in a glass jar with a lid. Take the prep a step further and make the chicken filling and the sauce ahead of time. You can still store the sauce in the glass jar and store the cooked chicken separately, in the refrigerator, in another food storage container.