Step 1

Preheat the oven to 350 degrees F.

Step 2

In a large saucepan over medium heat, melt the butter.

Step 3

Add the onion to the butter and cook until softened, about 5 minutes.

Step 4

Add the chicken, the black beans, the corn, the cream of chicken soup, the tomatoes with chilies (and their juices), the green chiles, the cream cheese, and the cilantro and cook until the cream cheese has melted, about 5 minutes.

Step 5

Layer 1/3 of the corn chips on the bottom of a 9x13-inch baking dish.

Step 6

Evenly add 1/2 of the chicken mixture to the top of the corn chips.

Step 7

Sprinkle 1/3 of the shredded cheese on top of the chicken mixture.

Step 8

Repeat the layers once, starting with the corn chips and ending with the shredded cheese.

Step 9

Top the shredded cheese with the remaining corn chips, and then top the corn chips with the remaining shredded cheese.

Step 10

Bake the casserole until the cheese has melted and begins to brown, about 30 minutes.

Step 11

Let the casserole sit for 30 minutes.

Step 12

Top with the sour cream and serve.