Preheat oven to 350F.
Place chicken breasts in a sauce pan and fill with water. Bring the pot to a boil, reduce to a simmer and cover the pot. Simmer for 14 minutes, remove the chicken breasts from the pot and allow to cool. When it has cooled slightly, shred the chicken with 2 forks.
Slice the corn tortillas into strips and then cut each strip in half. Set aside. Drain and rinse black beans.
Heat oil in a large oven safe skillet over medium heat and saute the onion and green chiles in the oil until the onions are soft about 3-4 minutes. Season with salt and pepper.
Add the black beans, shredded chicken and enchilada sauce to the skillet and toss to combine. Simmer for 5 minutes.
Turn off the heat and mix the cut up tortillas into the skillet and top with the shredded cheese.
Place in the oven and bake at 350F for 5-8 minutes or until the cheese is melted and bubbling.
