Toasted Chile Salsa

Heat a medium-sized iron skillet over high heat, utilizing it to sear the costeno amarillo chile peppers. Stir them constantly until they reach a deep, dark brown color. Be cautious not to let the peppers burn; this can ruin their flavor. Remove them from the heat source and set them aside to cool.

Submerge tomatillos in a medium-sized saucepan, ensuring they are completely covered with water. Bring the mixture to a rolling boil and cook for 5 minutes, or until they reach your desired level of tenderness. Remove the saucepan from the heat and let it drain any excess water.

Combine the cooked chile peppers, tomatillos, and garlic in a blender or food processor. Pulse until the ingredients form a smooth, uniform mixture.

Transfer this chile pepper mixture to a medium-sized bowl. Mix in the diced onion, chopped cilantro, and salt until well combined. Allow the mixture to chill in the refrigerator for a period of time before serving.