Add 1/2 of the frozen corn, topped with 1/3 of the scallions, then 1/2 of the chicken, and 1/2 of the cheese.
Repeat layers starting with the remaining tortillas, and ending with the remaining cheese.
Bake for 20 minutes, or until heated through and beginning to brown on top.
Top with remaining scallions before serving.
Vegetarian? I recommend substituting black beans and diced, steamed sweet potatoes for the chicken.
Make ahead- assemble ahead of time and refrigerate for up to 3 days until you are ready to bake. Freeze assembled casserole for up to 6 months in an airtight baking dish. Defrost in refrigerator for 24 hours before baking.
The provided nutrition information does not include any added sodium from seasoning to taste, any optional ingredients, and it does not take brands into account. Feel free to calculate it yourself using this calculator or by adding the recipe to Yummly.