In a skillet heat olive oil and butter over medium heat.
Cook onion about 5 minutes until they become soft and translucent.
Add diced bell pepper and garlic and cook approx 2 more minutes until they soften.
Add both the cans of soup, 1/2 cup of chicken stock, the shredded chicken, chili powder, cumin, pepper, cayenne and salt.
Stir to combine and heat through. Remove from heat.
In a 9x13 baking dish pour the remaining 1/2 cup chicken stock.
Tear 4 tortillas in half and arrange them evenly on the chicken stock in the pan.
Spread 1/3 of the chicken mixture over the tortillas.
Repeat this process 2 more times using all the mixture and all 12 tortillas.
Sprinkle the cheese on top and cover tightly with aluminum foil.
Bake casserole for 40 minutes. Let sit for 10 minutes before serving,