Preheat oven to 375°F and spray a 9x13 baking dish.
Blend all sauce ingredients until smooth and creamy.
Sauté the bell pepper and onion for 6-8 minutes.
Season with garlic powder, onion powder, and cumin.
In a large bowl, combine the chicken, sautéed vegetables, black beans, ¼ cup cheddar cheese, green onions, and about ¾ cup of the enchilada sauce.
Fill each tortilla with the chicken mixture, roll tightly, and place seam-side down in the baking dish.
Pour the remaining sauce over the enchiladas and top with the remaining 1 cup cheddar cheese.
Bake for 20-25 minutes, or until hot and bubbly.
Let cool for 5-10 minutes before serving, topped with Greek yogurt (or sour cream), salsa, and green onions.
