Preheat oven to 400 degrees F. Line a baking sheet with foil.

Cut the tomatillos in half and spread them out on the baking sheet. Toss in the chilies, garlic, onion, olive oil, salt, and black pepper until evenly combined and spread out in an even layer. Roast until charred, about 15 to 20 minutes. Remove from the oven and set aside to cool. Transfer to a blender, along with the chicken stock and cilantro and blender until smooth. Set a large pot over medium-high heat along with the canola oil. Once hot, pour the sauce in and cook until thick and reduced by half, about 1 hour. Stir in the shredded chicken, set aside.

To make the crust, in a medium bowl, whisk together the cornmeal, masa, flour, sugar, baking powder, baking soda, butter, buttermilk and eggs until smooth. Pour into a greased baking dish, spreading it out into an even layer. Top with the green chicken chili, spreading it out into an even layer as well.

Cook the pasta until al dente, according to the package directions. Drain and set aside. To make the cheese sauce, place a large saucepan over medium-high heat with the butter. Once melted whisk in the flour and cook for about 30 seconds, slowly stream in the milk, whisking until smooth. Cook over medium until thick, about 10 minutes. Season with salt, black pepper and chili powder. Remove from the heat and stir in 1 1/2 cups cheddar cheese, and 1 1/4 cups pepper jack until melted and smooth. Mix in the cooked noodles until well combined. Pour over the green chicken chili layer. Sprinkle the top with panko, and reserved cheeses.

Bake until bubbly and golden brown on top, about 25 to 30 minutes. Remove from the oven and let cool slightly before serving. Enjoy!