Heat a 10-inch ovenproof skillet, preferably cast iron, over medium heat. Add the chorizo and cook for 5–7 minutes, breaking it into small pieces, until browned and cooked through.

If the chorizo is unusually lean, add up to 1 tablespoon vegetable oil. If more than about 1 tablespoon of fat has rendered, spoon off the excess, then add the onion and poblano and cook for 4–5 minutes until softened.

Add the minced garlic and cook for about 30 seconds, stirring constantly so it becomes fragrant without scorching. Taste the mixture and add salt only if needed.

Spread the chorizo, onion, poblano, and garlic evenly across the skillet. For a layered presentation, reserve a little of the chorizo mixture and scatter it over the cheese after adding the topping.

Cover the mixture with the grated cheese, then place the ovenproof skillet under a hot broiler for 3–5 minutes. Broil until the cheese is fully melted, bubbling, and lightly browned, watching closely during the final minute.

Remove the skillet carefully, garnish with chopped cilantro and additional cilantro if desired, and serve immediately. Offer warm corn tortillas or sturdy tortilla chips while the cheese is at its most scoopable.