Step 1

First, Make the Roux. Start by heating the oil in a large pan over medium heat (or melt the butter if using butter). Add the flour and stir until it is incorporated. Stir constantly for 10 minutes until the roux begins to turn a light brown.

Step 2

Add the onion and peppers. Stir. Cook them down for 5 minutes to soften. The mixture will be somewhat pasty.

Step 3

Add the garlic and cook for another minute.

Step 4

Stir in the seasonings - chili powder, cumin, and a bit of salt and pepper.

Step 5

Stir in the chicken broth and fire roasted tomatoes. The mixture will thicken up slightly like a chunky sauce. Cook for 5 minutes to let the flavors develop.

Step 6

Remove from heat and stir in the sour cream or crema and cooked shredded chicken.

Step 7

Preheat your oven to 350 degrees F.

Step 8

Layer the Casserole. Set 4 tortillas into the bottom of a square casserole dish, then add a few scoops of the chicken and vegetable mixture. Add a layer of shredded cheese.

Step 9

Repeat with two more layers of 4 tortillas, the chicken and vegetable mixture, and a final layer of shredded cheese.

Step 10

Bake the casserole for 20-25 minutes, or until the cheese is nice and melty.

Step 11

Remove from heat and cool slightly. Garnish with your toppings and serve!