Combine the chicken, salsa and green chiles in a large pot over medium heat, stir everything to combine, and cook for 20 minutes until the chicken is cooked through. Remove the chicken, and using 2 forks, shred the chicken. Reserve all of the sauce.
Preheat the oven to 375 degrees F.
In a medium-large sized skillet, layer the ingredients, starting with a layer of sauce followed by 3 tortillas, ½ of the chicken, ½ of the black beans, ½ of the corn, ½ of the cheese.
Repeat for the second layer with the remaining sauce, tortillas, chicken, black beans, corn and cheese. Bake for 20 to 30 minutes uncovered, until bubbly and cheese has melted and started to brown on top.
Top with scallions and cilantro to serve. Cut into wedges as needed.