Gather all ingredients. Preheat the oven to 400 degrees F (200 degrees C).

Brown chorizo in an 8-inch cast-iron skillet, over medium, 5 to 7 minutes.

Using a slotted spoon, transfer to a paper-towel lined plate to drain. In the same skillet, add oil if needed and cook onion and chile pepper until softened, 5 to 8 minutes. Season with salt.

Stir in all but 2 tablespoons of the chorizo and sprinkle with Chihuahua cheese.

Bake in the preheated oven until cheese melts and bubbles, 8 to 10 minutes. If desired, broil 4 to 5 inches from the heat for 1 to 2 minutes or until top is beginning to blister.