Traditionally made in an underground oven (just saw this on 911 Lone Star), barbacoa meat (usually beef, sheep or goat) is a classic Mexican dish left to cook undisturbed overnight until the meat is very tender.
I have tried many variations throughout the years but I found that this slow cooker version is my absolute favorite. Cooked low and slow for 8-9 hours, the meat comes out incredibly melt-in-your-mouth tender, falling apart and shredding so easily.