Here is a recipe for barbacoa from a friend of mine. It is very good.
Take 10 LB. of beef cheek meat (cachete de res) and heavily season it with chili powder, black pepper, comino (Spanish for cumin) and salt.
Lay the meat directly on the racks in a barbeque pit preheated to 350 degrees and cook for 4 hours at 300 to 350 degrees.
Transfer the fully cooked meat to a 1/2 sized aluminum steam table pan (2 3/16" deep). It is very tough at this point. Pour in most of a can of beer (either pour out the rest or drink it, your choice), one can of Rotel diced tomatoes and chilis (include the juice), and the juice from one lime.
Seal the pan with foil and put in an oven preheated to 200 degrees. Braise for about 4 hours at 200. If the meat doesn't fall apart with a fork then braise it longer. If you braise at 300, it will be ready sooner. Braise it until it is fall-apart tender.
Eat on tortillas with fresh Pico de Gallo and Cilantro or for breakfast with scrambled juevos.
