01 - Preheat oven to 350°F (175°C). Grease a 9x13-inch baking dish.
02 - In a bowl, combine shredded chicken, 1 cup Monterey Jack cheese, 1/2 cup sour cream, green onions, garlic powder, ground cumin, salt, and black pepper until evenly blended.
03 - Melt butter in a saucepan over medium heat. Stir in flour and cook for 1 to 2 minutes until bubbling but not browned.
04 - Gradually whisk in chicken broth and cook, stirring, until slightly thickened, about 3 minutes.
05 - Remove saucepan from heat. Whisk in 1 cup sour cream, diced green chilies, onion powder, and 1/2 teaspoon salt until mixture is smooth.
06 - Spoon chicken filling evenly onto each tortilla. Roll up tightly and place seam-side down in greased baking dish.
07 - Pour prepared white sauce evenly over the rolled tortillas. Sprinkle with remaining 1 cup Monterey Jack cheese.
08 - Bake uncovered for 25 to 30 minutes, until the top is bubbly and lightly golden.
09 - Allow to cool briefly. Serve garnished with chopped cilantro and extra green onions.