Melt 4 tablespoons of butter in a saucepan over medium heat. Whisk in 1/4 cup of all-purpose flour for about 1 minute until bubbly, then gradually add 2 cups of chicken broth. Keep whisking until thickened (about 3-4 minutes). Stir in 1 cup of sour cream, 1 teaspoon of ground cumin, salt, and pepper to taste.

In a large bowl, combine 3 cups of cooked shredded chicken, 1 small diced onion, 1 can of diced green chiles, 1/4 cup of chopped fresh cilantro, and 1 cup of Monterey Jack cheese. Mix well to combine all the flavors.

Spread a thin layer of the white sauce across the bottom of a greased 9x13 inch baking dish. Fill each tortilla with about 1/3 cup of the chicken mixture, roll tightly, and place seam-side down in the dish.

Pour the remaining white sauce evenly over the assembled enchiladas and sprinkle with the remaining cheese (about 1 cup).

Preheat your oven to 350°F and bake the enchiladas uncovered for 25-30 minutes, until bubbly and the cheese is golden brown.

Once out of the oven, let the enchiladas cool for about 5 minutes. This resting period helps with easier slicing and serving.