In a large skillet over medium-high heat, cook the chorizo, breaking it up with a wooden spoon as it cooks, for about 8-10 minutes or until fully cooked and slightly crispy.
While the chorizo is cooking, warm the tortillas. Wrap them in a damp paper towel and microwave for 30 seconds, or heat them individually in a dry skillet for about 30 seconds per side.
To assemble, place a spoonful of cooked chorizo on each warm tortilla and top with a sprinkle of diced onion.
Serve immediately and enjoy!
