Preheat oven to 375°F, and spray a 13x9-inch baking dish with nonstick spray.
Heat a large skillet over medium heat. Add the butter. Add onion, bell pepper, and jalapeno pepper and cook, stirring often, until onion is translucent and peppers are tender. Add minced garlic, stir, and cook for 30 seconds. Stir in chili powder, cumin, red pepper flakes, salt, and black pepper; cook, stirring occasionally, 1 minute.
6 tablespoons unsalted butter, 1 yellow onion, 1 bell pepper, 1 jalapeno pepper, 2 cloves garlic, 1 tablespoon chili powder, 1 tablespoon ground cumin, ¼ teaspoon crushed red pepper flakes, 1 teaspoon kosher salt, ½ teaspoon ground black pepper
Sprinkle the flour over the vegetable mixture and cook, stirring constantly, 1 minute.
6 tablespoons all-purpose flour
Add the broth and lime juice and whisk. Increase heat to high and bring mixture to a boil, stirring constantly. Boil 1-2 minutes, stirring occasionally, or until thickened. Remove from heat and stir in green chile tomatoes and sour cream.
1¾ cups low-sodium chicken broth, 2 tablespoons fresh lime juice, 10 ounces diced tomatoes with green chiles, 1½ cups sour cream
In a large bowl, combine chicken and cilantro; add vegetable mixture and mix well.
5 cups chopped cooked chicken, 1 cup chopped fresh cilantro leaves
In a medium bowl, mix together both cheeses.
2 cups freshly shredded Monterey Jack cheese, 2 cups freshly shredded sharp cheddar cheese
Line the prepared casserole dish with one-third of the semi-crushed tortilla chips. Top with half of the chicken mixture and one-third of the cheese. Repeat the layers once with the last two layers being tortilla chips and cheese.
8 ounces tortilla chips
Spray a large sheet of aluminum foil with nonstick spray to loosely cover the casserole dish.
Bake at 375°F for 30 minutes. Uncover and bake another 10-15 minutes or until lightly browned and bubbly. Let stand 10 minutes before serving topped with the garnishes of your choice.
Freshly chopped cilantro, Dollops of sour cream, Fresh tomatoes