-
1
Score the fat cap of the skirt steak at 2 cm intervals to prevent curling on the grill. Combine lime juice, crushed garlic, salt, and beer if using. Coat the meat and allow it to marinate briefly — the marinade is a seasoning, not a braise; the beef flavour must remain dominant. Do not over-marinate.
-
2
Light the mesquite charcoal and allow it to reach full heat before placing any meat. Mesquite burns hotter than oak or hickory; the coals must be white-ashed and radiating intense heat. Hold your hand 10 cm above the grate — it should be tolerable for no more than two seconds. This is the flavour foundation of the dish; gas or briquette produces an inferior result.
-
3
Place the marinated steak directly over the mesquite coals on high direct heat. Grill until deeply charred on the exterior and medium-rare within — the outside must be char-forward, not merely browned. This is where the dish lives or dies: insufficient heat steams rather than chars, and the defining mesquite crust is lost.
-
4
Remove the meat from the grill and rest for a minimum of 5 minutes before cutting. The meat should feel firm at its edges and yielding at its centre when pressed. Resting is not optional — juices that run immediately from an unrested skirt steak render the taco dry.
-
5
Cut strictly against the grain, then chop the rested meat into small, irregular pieces for tacos de asada — not sliced portions. Skirt steak is extremely tough with the grain; the fibres must be severed short. The pieces should be moist and hold their shape without weeping.
-
6
Load the chopped meat into warmed flour tortillas. Serve alongside frijoles de olla and guacamole. The taco should carry the clean, direct flavour of beef, mesquite char, and citrus — uncluttered.