Preheat oven to 375ºF. Spray a 9x13x2-inch baking dish with cooking spray.
Remove skin from rotisserie chicken and discard. Remove meat from bones and chop the chicken.
Tear corn tortillas into bite-sized pieces.
Assemble the casserole by layering half of the chicken in the prepared baking dish. Top with half of the enchilada sauce, half of the sour cream, half of the tortilla, and half of the cheese. Repeat the layers.
Cover the casserole dish with aluminum foil and bake for 40 minutes. Remove the foil and bake an additional 10 minutes or until bubbly.