Prepare Chilies: Soak the dried chilies in hot water for about 15 minutes until softened.

Blend Marinade: In a blender, combine soaked chilies, chopped onion, garlic, and tomatoes, then blend until smooth.

Slow Cook Beef: Place the chuck roast in the crockpot, pour blended chili mix, add broth, vinegar, oregano, cumin, bay leaves, salt and pepper, set to low for 8-10 hours.

Shred Beef: Remove beef from the slow cooker, let cool slightly, then shred with two forks and return to broth.

Fry Tortillas: Heat oil in a skillet, dip each tortilla in broth fat and fry until golden and crispy, about 1-2 minutes per side.

Assemble Tacos: Fill each crispy tortilla with shredded beef, fold, and fry again briefly to crisp edges.

Serve: Serve tacos hot with remaining broth for dipping and garnish with cilantro, onions, and lime.