Preheat oven to 350 degrees F (175 degrees C).Advertisement
Combine the soups, chicken, green chiles, onion and sour cream in a medium size bowl. Set aside.
Rip tortillas into bite size pieces and layer 1/3 onto the bottom of a 9x13 inch baking dish. Layer chicken mixture on top, then a layer of cheddar cheese. Repeat two additional times, making sure to end with cheese on the top layer. Bake in preheated oven for about an hour and serve.