Preheat oven to 400°F and grease a 9x13-inch baking dish with nonstick spray. Set aside.

In a skillet over medium-low heat, combine shredded chicken, 1 cup chicken broth, 1 cup enchilada sauce, cilantro, and garlic powder. Simmer gently while preparing the masa.

In a large bowl, beat butter until creamy. Gradually add masa harina in portions, mixing after each addition. Stir in green chiles, salt, sugar, baking powder, and pepper.

Slowly add remaining chicken broth until the masa reaches the consistency of thick peanut butter. Adjust as needed.

Spread half of the masa mixture in the baking dish. Top with 3/4 cup cheese, the chicken filling, another 3/4 cup cheese, and the remaining masa.

Pour remaining enchilada sauce over the top and sprinkle with remaining cheese.

Cover with foil and bake for 30 minutes. Uncover and bake for 10 more minutes, until cheese is melted and bubbly.

Let cool slightly, garnish with cilantro, and serve warm.