1. Toast the dried chillies
   Put a dry frying pan over a medium heat. Toast the ancho, guajillo and chipotle chillies for 20–30 seconds on each side until fragrant. Do not let them burn, or they will taste bitter.
2. Soak the chillies
   Put the toasted chillies in a bowl and cover with boiling water. Leave for 15 minutes until softened, then drain. Keep a splash of the soaking water in case you need to loosen the sauce.
3. Blend the chilli sauce
   Put the softened chillies into a blender with the onion, garlic, cumin, smoked paprika, oregano, coriander, cinnamon, tomato purée, vinegar, Worcestershire sauce, sugar and 200 ml of the beef stock. Blend until smooth.
4. Season and brown the beef
   Season the beef with salt and black pepper. Heat the beef dripping, Wagyu fat or oil in a heavy casserole over a medium-high heat. Brown the beef in batches until well coloured on all sides, then lift it onto a plate.
5. Cook the chilli base
   Turn the heat down to medium. Pour the blended chilli sauce into the casserole and cook for 4–5 minutes, stirring often. It should darken slightly and smell deep, smoky and savoury.
6. Braise the beef
   Return the beef to the casserole. Add the remaining beef stock and the bay leaves. Stir well, scraping the base of the pan. Bring to a gentle simmer.
7. Slow cook until tender
   Cover with a lid and cook in the oven at 150°C fan for 3–3½ hours, or until the beef is completely tender and pulls apart easily with two forks. Check once or twice during cooking and add a splash of water or stock if it looks too dry.
8. Shred the beef
   Lift the beef out into a dish and shred it roughly with two forks. Skim a little fat from the top of the cooking liquor and keep it for frying the tacos. Remove the bay leaves.
9. Make the dipping broth
   Simmer the remaining cooking liquor on the hob for 5–10 minutes until slightly reduced. Taste and adjust with lime juice, salt, pepper or a little more vinegar. It should be savoury, smoky, lightly sharp and rich enough for dipping.
10. Moisten the shredded beef
    Spoon enough of the reduced cooking liquor over the shredded beef to make it juicy, but not wet. Keep the rest warm as the consommé-style dipping broth.
11. Build the tacos
    Warm a frying pan or flat griddle over a medium heat. Brush or dip one side of each tortilla lightly in the reserved chilli fat from the cooking liquor. Place the tortilla fat-side down in the pan, add shredded beef and a little cheese if using, then fold.
12. Toast until crisp
    Cook the tacos for 1–2 minutes per side until lightly crisp, golden and hot through. Work in batches and keep the finished tacos warm.
13. Serve
    Serve the tacos with bowls of the warm dipping broth, diced red onion, coriander, pickled onions, jalapeños, lime wedges and sour cream or crème fraîche if you like.

Multi-Cooker Option

Ninja Foodi / Multi-Cooker

1. Use Sear/Sauté – High to toast the dried chillies briefly, then soak them in boiling water separately.
2. Blend the chilli sauce as in the main method.
3. Use Sear/Sauté – High to brown the seasoned beef in beef dripping, Wagyu fat or oil. Work in batches for better colour.
4. Turn down to Sear/Sauté – Medium, add the blended chilli sauce and cook for 4–5 minutes, stirring often.
5. Add the browned beef, remaining stock and bay leaves.
6. Pressure cook on High for 60 minutes, then allow a 15-minute natural release before venting.
7. The beef should be fork-tender and ideally around 93–96°C internally if using a probe; this is the tenderness range where collagen has properly broken down.
8. Shred the beef, reduce the cooking liquor on Sear/Sauté – High, then use the broth and chilli fat for finishing the tacos.
9. To crisp the filled tacos in the Ninja, use Air Crisp at 200°C for 5–7 minutes, turning once if needed, or toast them in a frying pan for better control.