Start by seasoning the chicken breasts or tenderloins with your favorite spices. Place them into the Instant Pot along with the salsa verde, green chiles, and water.
Seal the Instant Pot lid and set it to cook on high pressure for 10 minutes. Once the cooking cycle is complete, allow for a natural release for about 5 minutes, then perform a quick release.
Carefully remove the chicken from the pot and shred it using two forks. Set it aside while you prepare the casserole layers.
In the bottom of a greased baking dish, spread a thin layer of green enchilada sauce. Place 4 corn tortillas over the sauce, overlapping them as needed. Layer half of the shredded chicken, then half of the remaining green enchilada sauce, and sprinkle with one cup of shredded cheese.
Add another layer of 4 corn tortillas, followed by the remaining chicken, enchilada sauce, and top with the remaining cheese. Finish with the last 4 corn tortillas, topping with any remaining sauce and cheese.
If you want a crispy top layer, place your casserole under the broiler for about 5-10 minutes or until the cheese is bubbly and golden brown.
