Combine all the ingredients in the slow cooker and cooker for at least 12 hours.
When ready, shred the meat with forks. If the sauce is a little thin, pour the remaining sauce into a sauce pan and boil rapidly until thickened.
Scatter the pork 'n' beans in a tortilla and drizzle with extra sauce. Fold both sides in and the top and bottom over. Put seam side down into a hot pan until browned, flip and cook on the other side. Serve with salad.