Arrachera is a signature cut of beef in the north of Mexico and especially in Monterrey. The cut is from the underside of the animal, either from the flank or plate. There seems to be no consistency in the definition and you find the cut being indicated as equivalent to hanger steak, which comes from the plate (the animals abdominal muscles near the diaphragm) or as flank steak (again underneath the animal but closer to the hind legs).
What I buy, which is sold as arrachera, is clearly hanger steak. It's a fairly ragged looking cut with a long grain. The restaurants which specialise in arrachera (like here for example) seem to use the thicker flank steak cut.
The steak, when served, is cut perpendicular to the long fibres to make it more tender. The meat has a much more intense taste than steaks from the relatively under worked muscles on the top of the animal. Though the common advice is to serve the meat rare to keep it tender, I don't agree, given the fibrous nature of the cut, unlike a regular steak it is actually more tender when well cooked.
I invested in a new grill an used the opportunity of it's first use to compare three different methods of preparing arrachera. For cooking I used mesquite charcoal, which is traditional, and gives a long even heat and is not as hot as the charcoal bricks I would be used to using at home. (I'd never go back to those pressed briquettes after working with lump charcoal like this!)
Arrachera in 3 Chile Adobo
The first was a cut of arrachera (which you can see in a previously posted picture) marinaded in a 3 Chile Adobo rub. I have covered adobos already, so I won't go into detail. The rub was made from toasted and soaked guajillo, ancho and cascabel chiles, along with garlic, black pepper, allspice, cinnamon clove cumin and salt.
The meat was slathered in the paste and left to marinade for a couple of hours before cooking
Arrachera Marinaded in Pickled Jalapeño and Tequila
This was something I picked up from the internet and you see lots of versions under the same theme. In this case the meat is marinaded using the contents of a can of pickled jalapeños and a slosh of tequila.
The meat, jalapeños, can liquor and the tequila were all dumped into a large zip-lock bag and stashed in the fridge until cooling time. Unlike the adobo the marinade has a lot of acid which should help to tenderise the meat.
The third, and simplest, approach was simply to season the meat with plenty of salt and dried Mexican oregano.I guess this was the control in the experiment.
Simple is best.