I just had a pile of buche that I bought from a Mexican market. In broken English, the guy told me it was pork neck meat. It was flat, about the size of a paper plate, somewhat thin, and extremely tender. It appeared to have been braised. He told me to put lime juice and salt on it. Salsa, too. So, I did. He only sells it on Sat/Sun, so this will be my weekend treat. Next time, however, it will be given a quick chop, and crisped a bit on the flat top, and put in a taco, or five. Google revealed buche to be esophagus/neck, stomach, or offal, in general. Photos next Saturday!