Preheat oven to 350 degrees. Spray a 9x13 baking dish with non-stick cooking spray. Pour ½ cup green enchilada sauce on the bottom of the pan and spread evenly.
In a large bowl, stir together shredded chicken, sour cream, cream cheese, green chilies, ¼ cup salsa verde, and 1 ½ cups shredded cheese. Mix well.
Slightly warm the corn tortillas in the microwave for about 10-15 seconds. *I place a damp paper towel on the top and bottom of the stack and wrap it around to keep the tortillas moist.
Divide the chicken sour cream mixture evenly among the center of each tortilla and roll each one up. Place seam side down in the prepared baking dish.
Pour the remaining green enchilada sauce over the pan of prepared enchiladas. Top with remaining 2 cups cheese.
Cover the pan with foil and bake for 20 minutes. Remove the foil and continue to bake for another 10-12 minutes until the cheese is slightly golden.
Serve with fresh avocado, diced tomatoes, sour cream, and fresh cilantro.