Preheat your oven to 375°F (190°C).
In a small skillet over medium heat, add the avocado oil and sauté the diced white onion until translucent, then add the minced garlic and cook for 1 more minute.
In a mixing bowl, combine the shredded chicken breast, sautéed onion and garlic, diced green chiles, sea salt, and black pepper.
Spread 2 tablespoons of the green enchilada sauce on the bottom of a small oven-safe baking dish.
Cut the corn tortillas into halves or quarters and layer half of them over the sauce.
Top the tortillas with half of the chicken and chile mixture, followed by half of the remaining enchilada sauce.
Repeat the layers with the remaining tortillas, chicken mixture, and sauce.
Sprinkle the shredded Monterey Jack cheese evenly over the top.
Bake for 15 to 20 minutes until the sauce is bubbling and the cheese has melted and turned slightly golden.
Garnish with fresh chopped cilantro before serving.