Heat your vegetable oil over medium-low heat in a small saucepan.

Once the oil has heated, add in the flour and chili powder. Stir the flour/chili powder mixture for a couple of minutes. 

Add in your tomato sauce, water, and spices.  Cook and stir the sauce for about ten to twelve minutes, or until it reaches a thick sauce consistency.

Preheat oven to 350 degrees F.

First, spoon some of the enchilada sauce into the bottom of a 13×9 pan.

On top of the layer of sauce, add a layer of flour tortillas.

Top the tortillas with half of the shredded pork and half of the pinto beans.

Sprinkle 1/3 of the cheese over the pork and beans. 

Add 1/3 of your homemade enchilada sauce. 

For the second layer, you want to repeat the same process.  Add the flour tortillas, the pork, the beans, and the cheese.  Top this off with more flour tortillas, the remaining enchilada sauce, and then more cheese.

Place your casserole into your pre-heated oven and bake for 30 minutes, or until nice and bubbly, and just like that you are finished!