If you love tamales but don't like the work that they require, this casserole is for you. It's super easy to put together and the taste is phenomenal. This has become one of my favorite casseroles to fix in a pinch.
Combine 1/4 cup of cheese and next 6 ingredients in a large bowl, stirring just until moist. Pour mixture into a 13x9-inch baking dish that has been sprayed with non-stick cooking spray.
Bake at 400 degrees for 15 minutes or until set. Pierce entire surface liberally with a fork; pour about 2/3 of the enchilada sauce over top. Top with chicken, drizzle remaining sauce over chicken and sprinkle with remaining 1 cup of cheese.
Return to 400 degree oven and bake for 15 minutes or until bubbly and cheese has melted. Remove from oven and let stand for 5 minutes. Cut into squares and top with sour cream, diced tomatoes and diced avocado if desired.