Preheat your oven to 350F.
Add two tablespoons of oil to a medium skillet and heat over medium-high heat.
Once hot, add your diced onions and garlic and saute them in a pan for about 3-5 minutes.
Once cooked, add your chorizo and cook for 5-7 minutes, breaking it apart as you stir. Take off the heat once the chorizo is fully cooked.
In an oven safe dish or cast iron, place half of your cheese (2 cups) on the bottom of the dish. Next, add a layer of your cooked chorizo. Finally, top it off with the remainder of the cheese and cook in the oven for 20-30 minutes, until the cheese is melted and slightly browned on top.
Once out of the oven, top off the queso fundido with the remaining cooked chorizo, some fresh pico de gallo and cilantro.
Serve with either tostito chips or bread and enjoy!