Melt the butter and bacon grease in a cast iron skillet, over medium heat. Add the tomatillos and cook for about 5 minutes, then flip and cook for another 3 to 4 minutes, or until they are softened and charred slightly. Add the onion and cook on both sides for about 3 to 4 minutes.

Roast the peppers over a fire or in the skillet, until blackened. Place in a sealed plastic sack with a tablespoon of water and seal up. Let it set for about 10 minutes.

Remove from the sack and peel off the skins. Remove the seeds from the jalapeno, if desired.

Place the tomatillos, peppers, onion and garlic in the blender and blend until smooth. Add the cumin, oregano and chicken broth and blend again. Taste the mixture and season with salt and pepper, to taste.

Preheat the oven to 350 degrees F. Butter a 9x13-inch baking dish.

For the enchiladas: In a cast iron skillet over medium heat, melt the butter. Add the garlic and cook for about 1 minute, stirring constantly. Stir in 1 ½ cups of the chile verde sauce and cook for another 2 minutes. Remove from the heat and stir in the sour cream, chicken and 1 ½ cups of the cheese.

Pour half of the remaining verde sauce in the bottom of the baking dish. Spoon about 2 heaping tablespoons of the chicken mixture into the center of the corn tortillas and then roll up, place in the pan, seam-side down. Repeat with the remaining ingredients. Tip: warm the tortillas slightly before assembling to prevent cracking.

Pour the remaining sauce over the tortillas and top with the remaining cheese.

Cover the dish with aluminum foil and bake for 15 minutes. Remove the foil and bake for another 10 to 15 minutes, or until the cheese is melted and browned slightly.

Allow them to cool about 10 minutes before serving