Cut the chuck roast into large chunks and season with salt, pepper, cumin, and oregano. Sear the beef in a hot skillet for about 3 minutes on each side until browned. Transfer to the crockpot.

Soak the dried chilies in hot water for about 15-20 minutes until softened, then blend with garlic, onion, and some soaking water until smooth. Pour over the beef in the crockpot.

Pour the beef broth into the crockpot covering the meat, and add bay leaves and any remaining garlic. Stir gently and set the slow cooker on low for 6 to 8 hours.

After cooking, remove the beef and shred it with two forks. Return it to the broth and stir well.

Warm the tortillas on a skillet for about 30 seconds on each side until pliable. Keep warm in a kitchen towel.

Assemble tacos with shredded beef, topped with chopped onions, cilantro, and a squeeze of lime. Serve with salsa.