You need cheese (whatever you prefer, I used cheddar jack), black beans, tortillas (corn or flour), and enchilada sauce. I usually cook a big pot of beans and then freeze them in quart bags, usually a cup. You can use a can of them also. Whatever is easiest!
Then you repeat as many times as you like until there are tortillas on top then sauce, then cheese.
It should look like this:
Then you bake it covered with foil for 20 minutes, then uncovered for 10.