Consider this a model for brisket tacos, not gospel. But you do need to have a fully smoked and ready brisket to make them. I have instructions for smoked brisket here.
3 to 10chile pequins,or other small, hot, green chile
Juice of a lime
Water
Instructions
Slice the brisket thick, like 1/2 inch. Heat the beef fat or other cooking fat in a large pan, like a cast iron pan, and get it hot. Sear the slices of brisket on one side to crisp it up. Chop it all small enough to be a nice taco meat and keep it warm.
Heat a comal or griddle over medium-high heat. When it's hot, lay down some shredded cheese in a pile, somewhere around 2 or 3 tablespoons, depending on the size of your tortillas. When it starts to melt, set the tortilla over it and press down. Keep pressing down until you see the cheese reach the edges of the tortilla, or when cheese grease seeps out the sides. Let this cook for a minute or two, then, either using your hands or a metal spatula, remove the tortilla with the grilled cheese attached. This takes a little practice to perfect.
Now spread some guacamole over the cheese, then top with the brisket. Add the salsa of your choice and some cilantro and you're ready to rock!
PEQUIN SALSA
To make this, you grind the chiles and salt in a mortar or molcajete into a paste, then stir in the lime juice. If it's way too sharp and spicy for you (it's supposed to be both), add a splash of water.
Notes
There are lots of recipes for guacamole out there. This one is my favorite.For other salsa options, you can make a pico de gallo (tomatoes, cilantro, white onions, serrano chiles and lime juice), or try a salsa morita or a hot arbol chile salsa.