Preheat oven to 375.
Spray large baking dish.
Ladel in 3/4c sauce on the bottom. Top with 4 corn tortillas, cut in half/quarters to cover bottom of the dish.
Add 1 can black beans, 1/2 can Rotel, 3/4c onions and peppers, 1 green onion.
Layer 1/2 chicken over veggies and top with 1/2c shredded cheese.
Place an additional layer of 4 corn tortillas, cut in half, on top. Add 3/4c sauce.
Add 1 can black beans, 1/2 can Rotel, 3/4c onions and peppers, 1 green onion. Layer 1/2 chicken over veggies. Top with 1/2c shredded cheese.
Place a final layer of 4 corn tortillas, cut in half, on top. Top with remaining sauce.
Cover with tin foil and bake for 20 min.
Remove tin foil. Sprinkle on 1/2c cheese and remaining green onions. Bake an additional 10 min.