Soak the dried chilies in hot water for about 15 minutes until soft and pliable. Blend with chopped onion, garlic, and canned tomatoes until smooth.

Place beef chuck roast in slow cooker, pour blended chili mixture over the beef, and add broth, apple cider vinegar, oregano, cumin, bay leaves, salt, and pepper. Mix gently.

Cover and slow cook on low for 8-10 hours until beef is tender and easily shredded.

Remove beef and shred with two forks. Mix shredded beef back into the sauce.

Heat oil in a skillet. Dip tortillas in broth, then fry until crispy, about 1-2 minutes per side.

Fill each tortilla with the shredded beef mixture and fold. Optionally fry again until golden brown.

Serve warm with remaining broth for dipping, garnished with cilantro and onions.