Prepare the ingredients by shredding the cooked chicken.
In a large bowl, combine the shredded chicken, black beans, corn, half the cheese, bell peppers, cumin, chili powder, and salt and pepper.
Layer the bottom of the crockpot with a small amount of enchilada sauce.
Spoon half of the chicken mixture over the sauce and top with crushed tortilla chips.
Pour half of the remaining enchilada sauce on top of this layer.
Repeat the layers with the remaining chicken mixture, crushed chips, and finishing with enchilada sauce.
Top the casserole with the remaining shredded cheese.
Cover and cook on low for 4-6 hours or high for 2-3 hours until everything is heated through.
Once done, serve warm garnished with cilantro, sour cream, or avocado if desired.