Preheat oven to 400 degrees and grease a rectangular casserole dish.
Heat a 1-2 T olive oil in a large nonstick skillet over medium high heat. Add ground beef and cook, breaking up with the back of your spoon until fully cooked through. Season to taste with salt and pepper to taste. Discard any excess grease.
Add beans and 1 cup enchilada sauce to skillet and toss to combine. Remove from heat.
Scatter half of the beef mixture into the bottom of your greased casserole dish, followed by 3/4 cup cheese and two tortillas. Top with remaining beef mixture, another 3/4 cup cheese, two tortillas, and the remaining enchilada sauce and 3/4 cups cheese.
Cover with foil and bake for 25 minutes, remove foil and bake another 10 minutes.