Place all ingredients in a slow cooker and cook for 8-10 hours on low or high until meat is fork-tender. Separate meat from sauce and place in containers to refrigerate. Skim fat from meat and sauce. Cook sauce over medium heat until it thickens to desired consistency. Shred beef and heat to use in taco, tortillas, etc. May also substitute barbecue sauce for a less spicy flavor. Serve with Mexican or Spanish rice and black or pinto beans. Yield: 8-10 servings.