Preheat the oven to 350°F (175°C) and spray a 9x13-inch baking dish with cooking spray.
In a mixing bowl, combine 3 cups chopped cooked chicken, 2 cups shredded Pepper Jack cheese, 1/2 cup sour cream, the 4-oz can diced green chilies, and 1/3 cup chopped cilantro until evenly mixed.
Spoon an even portion of the chicken mixture down the center of each 8-inch flour tortilla and roll tightly. Place seam-side down in the prepared baking dish.
Bake the enchiladas for 30–35 minutes, or until they are heated through and lightly golden on top.
While the enchiladas bake, whisk together 1/2 cup sour cream and 1/2 cup salsa verde until smooth.
Pour the salsa verde–sour cream mixture evenly over the baked enchiladas, then return the dish to the oven and bake an additional 5–10 minutes until warmed through.
Notes
Rotisserie chicken works well as a shortcut.
Feel free to substitute corn tortillas if preferred.
Use Monterey Jack cheese for a milder flavor.
You can replace salsa verde with a can of green enchilada sauce.
Omit cilantro if desired.
Additions: chopped white onion, lime juice, black beans, garlic, or ground cumin/taco seasoning.