Preheat your oven to 375°F and line a large baking sheet with foil for easy cleanup. Spread half the tortilla chips across the sheet in an even single layer, creating a solid foundation for your toppings and ensuring even heat distribution.

Combine the shredded chicken with BBQ sauce in a small bowl, stirring until every piece is evenly coated with that smoky, sweet glaze. Set aside for exactly 2 minutes to allow flavors to meld before the next step.

Distribute the BBQ chicken evenly across the tortilla chips, then sprinkle half the shredded cheddar cheese over top. Add the black beans and corn across the layer, spreading them to ensure every chip gets some protein and vegetables.

Place the baking sheet in the oven and bake for exactly 12-15 minutes until the cheese melts completely and begins to bubble at the edges. This is your critical timing window—watch through the oven window if needed, as cheese can brown quickly.

While cheesy loaded BBQ nachos cook, whisk together sour cream, salsa, lime juice, and diced red onion in a small bowl until smooth and combined. This fresh topping stays cool and bright, providing the perfect counterbalance to hot, melted cheese.

Remove the baking sheet from the oven and let it cool for exactly 2 minutes before adding remaining chips around the edges. This keeps the fresh chips from getting soggy while allowing you to distribute heat evenly.

Top with the sour cream mixture, jalapeños, and fresh cilantro for final garnish and vibrant color. Serve immediately while the cheese remains gooey and satisfying for your eager crowd.