Beef Enchilada Casserole

I made this for my family the other night, and everyone enjoyed it.

Ingredients
1 lb ground beef
1/2 cup onion, chopped
2 cans of tomato sauce (8 oz each)
1 can of black beans (15 oz)
1 can of chopped green chiles (4.5 oz)
6 flour tortillas (8 oz)
2 cups shredded Mexican-style cheese
2 tsp chili powder
1 tsp cumin
1 tsp minced garlic
1/2 tsp Oregano leaves

Instructions
Cook the beef and onion in a large skilled until the beef is browned all the way through and the onions are crisp-tender.
Drain and rinse the beans, and add them to the skillet.
Add the tomato sauce and green chiles to the beef mixture.
Mix all ingredients well, then stir in all the spices and bring the mixture to a boil, stirring.
Reduce heat to low, and simmer for five minutes.

Begin pre-heating your over to 350 degrees.

Spray a 13x9x2-inch baking dish with non-stick spray.
Spread 1/2 cup of beef mixture on the bottm of the baking dish.
Top the beef mixture with three tortillas. They may overlap if needed.
Spread half of the remaining beef mixture over the tortillas.
Spread 1 cup of cheese over the beef mixture.
Top with three more tortillas.
Spread the remaining beef mixture over the tortillas.
Spread the remaining cheese over the beef mixture.

Bake the casserole for fifteen minutes, until heated through and cheese on top if melted.
Remove the casserole from the oven, and let it site for 5 minutes before serving, so that it can set and be cut into pieces more effectively.

Notes
For a healthier version, replace the flour tortillas with whole wheat tortilles.
This makes eight servings.