01 - Preheat the oven to 350°F (175°C) and lightly grease a 9x13-inch baking dish.
02 - In a mixing bowl, thoroughly combine shredded chicken, 1 cup Monterey Jack cheese, 1/2 cup sour cream, green onions, garlic powder, ground cumin, salt, and black pepper.
03 - Melt unsalted butter in a saucepan over medium heat. Add all-purpose flour and whisk constantly for 1-2 minutes until bubbling but not browned.
04 - Gradually add chicken broth, whisking continuously. Cook for about 3 minutes until the mixture is slightly thickened.
05 - Remove saucepan from heat. Incorporate sour cream, diced green chilies, onion powder, and additional salt. Whisk until the sauce is velvety and smooth.
06 - Divide the chicken filling evenly among the flour tortillas. Roll each tortilla and place seam-side down in the prepared baking dish.
07 - Pour the white sauce evenly over the filled tortillas. Sprinkle the remaining 1 cup Monterey Jack cheese on top.
08 - Bake uncovered for 25-30 minutes, until the cheese is bubbly and golden. Remove from oven and let cool briefly.
09 - Garnish with chopped cilantro and additional green onions before serving.