I had this in a restaurant in California. Excellent. I asked the chef for the recipe.
Preheat oven to 350 degrees. Spray a 13x9-inch pan with the cooking spray. In a large bowl, stir together the 3 kinds of soup and the tomatoes. Stir in the chicken. Layer the tortillas and the chicken mixture in the pan, beginning and ending with tortillas. Sprinkle the cheese over the casserole and bake for 30 minutes.