Remove stems and seeds from the dried chilies. Toast them lightly in a dry skillet over medium heat until fragrant. Soak the toasted chilies in hot water for about 20 minutes until softened.
In a blender, combine the soaked chilies, onion, garlic, cumin, oregano, cinnamon, vinegar, and a pinch of salt and pepper. Blend until smooth, adding soaking water if necessary to achieve a sauce-like consistency.
Place the beef chunks in a large bowl or zip-top bag. Pour the marinade over the meat, ensuring all pieces are well coated. Cover and refrigerate for at least 4 hours, preferably overnight.
Transfer the marinated meat and marinade into a slow cooker. Add the beef broth. Cover and cook on low for 6-8 hours, or until the meat is tender and easily shredded.
Remove the meat from the slow cooker and shred it using two forks. Strain the cooking liquid to use as a dipping sauce (consommé).
Heat a skillet over medium heat. Dip each tortilla briefly into the consommé to coat. Place the dipped tortilla on the skillet and add a portion of shredded meat. Top with chopped onion, cilantro, and cheese if using. Fold the tortilla in half and cook until crispy on both sides.
Serve the tacos hot with lime wedges and a side of the reserved consommé for dipping.