Start with beef that is browned, not saucy or over-marinated
pepper, garlic powder, and onion powder are enough when the taco is also bringing browned cheese, tortillas, salsa, and onion. If the beef tastes muddy or wet, the cheese crust has to fight too hard for attention.
This also means the pan should stay hot enough to brown the beef instead of steaming it. Crisp cheese tacos work best when the filling is loose and savory, not when it drips onto the comal and softens the crust from underneath.
If you are using leftover carne asada instead of fresh diced beef, warm it just enough to loosen it. Do not keep cooking it until it dries out, because the taco already has enough crispness coming from the cheese side.


