Preheat the oven to 375 degrees and lightly grease a 9x9 baking dish.
Warm a skillet over medium heat and cook the diced onion with the cumin for 3 minutes until the onion softens.
In a large bowl, combine the shredded chicken, black beans, cooked onion, and 1 cup of enchilada sauce.
Spread 1/4 cup of the remaining enchilada sauce across the bottom of the baking dish.
Layer 2 corn tortillas over the sauce, then spread half the chicken mixture on top and sprinkle with 1/2 cup cheese.
Repeat the layers once more with 2 tortillas, the rest of the chicken mixture, and another 1/2 cup cheese.
Top with the final 2 tortillas, the remaining 3/4 cup enchilada sauce, and the last 1/2 cup cheese.
Cover the dish with foil and bake for 20 minutes, then remove the foil and bake 10 more minutes until the cheese is bubbly.