Preheat the oven to 375˚. Melt the butter in a 12-inch cast-iron skillet over medium-low heat. Add the onion and cook until golden brown, 8 minutes. Remove the skillet from the heat and stir in the enchilada sauce, green chiles, and adobo sauce. Remove all but 2 tablespoons of the sauce to a bowl and reserve. Cover the sauce in the skillet with 4 tortillas so that they overlap slightly in the center and come up the sides a little. Top the tortillas with 1¼ cups cheese and half of the corn. Dollop half of the refried beans on top and drizzle with ½ cup of the reserved green sauce. Add 4 more tortillas and repeat the layering process with 1¼ cups cheese, the remaining corn, the remaining beans, and ½ cup green sauce. Top with the remaining 5 tortillas and the remaining green sauce and cheese. Cover the skillet with foil and bake until hot and bubbly, about 35 minutes. Remove the foil and bake until set, another 10 minutes. Let stand about 10 minutes before serving. Top with pico de gallo and cilantro.