Step 1: Prepare the Southwest Chicken Filling
Preheat your oven to 375°F (190°C). Grease a 9×13 inch (23x33cm) baking dish. In a very large bowl, combine the shredded chicken, cooked Spanish rice, drained black beans, drained corn, undrained green chiles, salsa, cumin, chili powder, smoked paprika, and lime juice. Mix gently until everything is evenly combined. This is your flavor-packed filling base.

Step 2: Create the Creamy Cheese Layer
In a separate bowl, beat the softened cream cheese, sour cream, and optional ranch dressing together with a hand mixer or sturdy whisk until completely smooth and creamy.

Step 3: Assemble the First Layer
Spread about one-third of the chicken and rice mixture evenly in the bottom of the prepared baking dish. Dollop half of the creamy cheese mixture over the top and spread it gently into an even layer. Sprinkle with 1 cup of the Monterey Jack cheese and ½ cup of the cheddar cheese.

Step 4: Add the First Tortilla Layer
Place a layer of flour tortillas over the cheese, tearing them as needed to fit and completely cover the surface. Lightly spray the tortillas with cooking spray or brush with melted butter (this helps them crisp slightly).

Step 5: Build the Second Stratum
Spread half of the remaining chicken and rice mixture over the tortillas. Sprinkle with another 1 cup of Monterey Jack and ½ cup of cheddar cheese.

Step 6: Repeat with Final Layers
Add another layer of tortillas (spray/butter again). Spread the remaining chicken and rice mixture. Dollop and spread the remaining creamy cheese mixture over the top. Sprinkle with the final 1 cup of Monterey Jack and the final 1 cup of cheddar cheese.

Step 7: Apply the Final Topping and Bake
Place a final layer of tortillas on top. Spray or butter lightly. Sprinkle the reserved 1 cup of cheddar cheese evenly over the entire surface. Cover the dish tightly with aluminum foil.

Step 8: Bake, Uncover, and Finish
Bake, covered, for 25 minutes. Then, remove the foil and bake for an additional 15-20 minutes, or until the cheese is completely melted, bubbly, and the top is lightly golden brown. If you desire a more golden top, broil for the final 1-2 minutes, watching carefully.

Step 9: Garnish and Serve Fiesta-Style
Remove the bake from the oven and let it rest for 10-15 minutes. This rest is crucial for the layers to set for clean serving. Just before serving, garnish the entire top with sliced green onions, diced tomato, avocado, cilantro, and olives (if using). Serve directly from the dish, passing sour cream for drizzling, extra salsa, and lime wedges at the table so everyone can customize their plate.