In a large bowl, combine the tortilla chips, corn, black beans, diced chicken, cheese, salsa, scallions, and taco seasoning. Stir it all together very well, being careful not to crush the tortilla chips too much. Taste the mixture and adjust seasoning if necessary (and keep in mind this will taste wetter than when it comes out of the oven).
Pour the entire mixture into an 8×12 or 9×13 casserole dish, and cover tightly with foil. Bake for 30 minutes, then serve with your favorite garnishes (like avocado slices, sour cream, fresh chopped tomatoes, scallions, etc). Enjoy!