If you have never tried Beef tongue Barbacoa, this is the easy way to go. The texture is soft that almost melts in your mouth. The leftovers if any, are great for sandwiches, flautas, scramble with eggs, etc. It also freezes well.
Rinse the beef tongue with water and place in your crockpot, add onion, garlic, bay leaf, salt, and water. Cover and set the crockpot on low for 8 hours. Cook until tender. If after 8 hours the meat is not tender enough to shred cook a little bit longer. Not all Crockpots work alike.