01 - Preheat oven to 350°F (175°C). Lightly grease a 9x13-inch baking dish.
02 - In a mixing bowl, blend shredded chicken, 1 cup Monterey Jack cheese, 1/2 cup sour cream, green onions, garlic powder, cumin, salt, and pepper until uniformly combined.
03 - Melt butter in a saucepan over medium heat. Add flour and stir for 1–2 minutes until the mixture is bubbling but not browned.
04 - Gradually whisk in chicken broth. Cook, stirring continuously, until slightly thickened, approximately 3 minutes.
05 - Remove saucepan from heat and whisk in sour cream, diced green chilies, onion powder, and salt until the sauce is smooth.
06 - Fill each tortilla with a portion of the chicken mixture, roll tightly, and arrange seam-side down in the prepared dish.
07 - Pour the white sauce evenly over the filled tortillas. Sprinkle with the remaining 1 cup Monterey Jack cheese.
08 - Bake uncovered for 25–30 minutes, until enchiladas are bubbling and the cheese is lightly golden.
09 - Allow to cool slightly before garnishing with chopped cilantro and extra green onions. Serve warm.