Meanwhile, heat a cast-iron skillet on the stovetop over medium to high heat. While warming, add the chorizo and break it into chunks with a wooden spoon. Cook over medium heat, turning until cooked through and lightly browned, about 8 minutes. Remove the chorizo to a plate.
Drizzle olive oil and add the onions and bell peppers to the pan juices and cook until tender, about 5 minutes. Return the chorizo to the skillet with the onions and bell peppers and stir to combine.
Sprinkle cheese in the skillet.
Bake until the cheese is bubbling, about 15 minutes. Serve with flour or corn tortillas for soft tacos or with tortilla chips.
Cheese: I recommend one pound of a combination of shredded Mexican-style melty cheeses, such as queso Oaxaca, asadero or enchilado. Feel free to substitute with mozzarella and muenster.
Make ahead tip: This can be prepared a couple hours ahead then popped in the oven when it's fiesta time.