Preheat your oven to 375°F (190°C) and lightly grease a 9x13 inch baking dish with cooking spray.
In a large mixing bowl, whisk together the sour cream, mayonnaise, lime juice, garlic powder, ground cumin, and 1 teaspoon of the chili powder until smooth.
Add the shredded chicken, corn kernels, and 1 cup of the shredded Pepper Jack cheese to the bowl. Stir well until the chicken and corn are evenly coated in the sauce.
Transfer the mixture to the prepared baking dish and spread it out into an even layer.
Top evenly with the remaining 1 cup of Pepper Jack cheese.
Bake uncovered for 20-25 minutes, or until the casserole is bubbly and the cheese has melted.
Remove from the oven and immediately sprinkle the crumbled Cotija cheese and the remaining 1 teaspoon of chili powder over the top.
Garnish generously with fresh chopped cilantro and serve warm with extra lime wedges.