01 - Scatter the chopped onion and minced garlic evenly across the bottom of the slow cooker insert.
02 - Nestle the trimmed chuck roast chunks on top of the onion and garlic bed.
03 - In a small mixing bowl, whisk together the chopped chipotle peppers, lime juice, ground cumin, dried oregano, smoked paprika, salt, black pepper, apple cider vinegar, and beef broth until well combined.
04 - Pour the marinade evenly over the beef pieces. Tuck the bay leaves into the liquid around the meat. Secure the lid and cook on low for 8 hours, or until the beef is fork-tender and shreds effortlessly.
05 - Discard the bay leaves. Using two forks, shred the beef directly in the slow cooker, stirring to absorb all the cooking juices throughout the shredded meat.
06 - Serve the barbacoa hot with warm tortillas, over steamed rice, in burrito bowls, or however you prefer.