01 - Preheat oven to 375°F. Grease a 9x13-inch baking dish with cooking spray or butter.
02 - Heat olive oil in a large skillet over medium heat. Sauté diced onion and red bell pepper for 3-4 minutes until softened. Add minced garlic and cook for 1 minute until fragrant.
03 - Add shredded chicken, drained black beans, diced green chiles, and taco seasoning to the skillet. Mix thoroughly and cook for 2 minutes to combine flavors. Remove from heat.
04 - In a large mixing bowl, whisk together sour cream, cream of chicken soup, whole milk, ground cumin, paprika, salt, and black pepper until smooth and well combined.
05 - Spread a thin layer of creamy sauce on the bottom of the prepared baking dish. Arrange 4 tortillas over the sauce, overlapping as needed to cover the surface.
06 - Distribute half of the chicken and bean mixture evenly over the tortillas. Drizzle with one-third of the creamy sauce. Sprinkle with one-third of the cheddar and Monterey Jack cheeses.
07 - Repeat with another layer of 4 tortillas, remaining chicken mixture, another third of sauce, and another third of cheeses.
08 - Top with remaining 4 tortillas, remaining sauce, and remaining cheeses. Ensure the top layer is evenly coated.
09 - Cover the baking dish tightly with aluminum foil. Bake for 25 minutes until heated through and bubbling around edges.
10 - Remove foil and bake for an additional 10 minutes until cheese is melted, bubbly, and lightly golden on top.
11 - Let the lasagna rest for 10 minutes before slicing to allow layers to set. Garnish with fresh chopped cilantro. Serve warm.