Preheat the oven to 350°F.
Heat the oil in a skillet and saute the bell peppers and onion for 2 minutes, then transfer into a bowl.
Add both cans of soup to the bowl, along with the Rotel tomatoes, broth, cumin, sour cream, ancho and chipotle chile powders, and oregano.
Stir until well combined.
Spread a few tablespoons of this mixture in the bottom of a 9 x 13-inch baking dish, then top with half the chicken, half the sauce, half the cheese and half the tortilla quarters.
Add the rest of the chicken on top of that and then all except ½ cup of the rest of the sauce.
Top that with half the remaining cheese and the rest of the tortillas.
Add the rest of the sauce on top followed by the rest of the cheese.
Bake for about 40 minutes until golden brown and bubbling.
Broil for a couple of minutes if you want the top more crisp, then serve hot.