Preheat the oven to 350°F (175°C). Grease a 9x13-inch baking dish with butter or cooking spray.

In a large mixing bowl, combine shredded chicken, garlic powder, onion powder, cumin, salt, and pepper. Stir to distribute the seasonings evenly throughout the chicken.

Add 1 cup of shredded Monterey Jack cheese to the seasoned chicken and mix well. Set aside.

Warm the tortillas by wrapping them in a damp paper towel and microwaving for 30-45 seconds, or heat them one at a time in a dry skillet for 15 seconds per side.

Lay a tortilla flat and spoon about 1/4 cup of the chicken mixture into the center. Roll the tortilla tightly and place it seam-side down in the prepared baking dish. Continue with remaining tortillas.

Melt butter in a medium saucepan over medium heat. Stir in the flour and whisk constantly for about 1 minute until it forms a smooth paste.

Gradually whisk in the chicken broth, stirring continuously to prevent lumps. Cook for 3-4 minutes until the sauce thickens enough to coat the back of a spoon.

Remove the pan from heat and stir in the sour cream and diced green chilies until smooth. Taste and adjust seasoning if needed.

Pour the prepared sour cream sauce evenly over the enchiladas, making sure to cover all tortillas.

Sprinkle the remaining 1 cup of shredded Monterey Jack cheese over the top.

Bake uncovered for 20-25 minutes, or until the cheese is melted and the sauce is bubbly around the edges.

Remove from oven and let rest for 5 minutes. Garnish with fresh cilantro before serving.