Heat oven to 350°F. Spray 9-inch glass pie plate or 9 1/2-inch deep-dish glass pie plate with cooking spray.
In medium bowl, mix cooking sauce and salsa. In second medium bowl, mix chicken and corn. Spread one-fourth of sauce mixture in pie plate. Top with 2 tortillas, one-fourth each of the sauce mixture, chicken mixture and cheese. Repeat layers 2 more times (using 3 tortillas for remaining layers), starting with tortillas and ending with cheese on top. Pie plate will be very full but should not overflow.
Bake about 30 minutes or until hot in center and cheese is melted and lightly browned around edges. Let stand 5 minutes before serving. Top each serving with sour cream, avocado and olives.