Heat oil in a nonstick pan over medium heat. Add onions, jalapenos, and chorizo to pan, cook, breaking up with spoon until fully cooked, about 5-7 minutes.

In a bowl combine diced tomatoes, and cilantro; stir to combine.

Set aside until ready to use.

Preheat broiler.

With a slotted spoon divide chorizo-onion, jalapeño mixture into four individual oven safe serving dishes, top each dish with tomato and cilantro and top with cheese.

Broil until cheese is melted, about 5 minutes.

Serve warm with tortillas or tortilla chips.