Heat 1 tbsp (15ml) of olive oil in a large skillet over medium-high heat. Season the diced chicken breasts with salt and pepper. Sear for 3-4 minutes undisturbed to form a crust, then toss and cook for another 3 minutes until fully cooked and juicy. Transfer to a plate.

In the same skillet, add the remaining 1 tbsp (15ml) of olive oil over medium-high heat. Add the sweet corn kernels in an even layer. Let cook undisturbed for 3 minutes to blister, then toss and cook for 2 more minutes until beautifully charred and golden. Remove from heat.

In a large bowl, whisk the softened cream cheese, sour cream, and mayonnaise until completely smooth. Slowly whisk in the whole milk, minced garlic, salt, and pepper until you have a thick, creamy white sauce.

Preheat your oven to 375°F (190°C). Fold the cooked chicken breast chunks and charred sweet corn into the creamy white sauce until evenly coated. Transfer the mixture to a rustic ceramic baking dish and spread evenly.

Bake uncovered for 20-25 minutes. The casserole is ready when the sauce is aggressively bubbling and the edges are slightly browned and caramelized. Let rest for 5 minutes after removing from the oven.

Generously sprinkle the top layer with crumbled white cotija cheese. Finish with a vibrant dusting of red chili powder and freshly chopped green cilantro leaves right before serving.