Prepare the dried chillies. Place the dried ancho chillies in a heatproof bowl and cover them with boiling water. Let them soak for 15 minutes until they become soft and pliable, like a piece of leather. Once softened, drain them and set aside.

Brown the beef. Heat the oil in a large, heavy-based pot or Dutch oven over a medium-high heat. Pat the beef chunks dry with kitchen paper—this is crucial for a good sear. Working in batches to avoid overcrowding, add the beef and cook for 3-4 minutes per side, until a deep, mahogany-brown crust forms. You'll hear a satisfying sizzle, and the kitchen will fill with a rich, savoury aroma. Transfer the browned beef to a plate.

Sweat the aromatics. Reduce the heat to medium. Add the chopped onion to the pot and cook for 5-6 minutes, stirring occasionally, until it becomes translucent and softens. The edges should just start to turn golden. Add the minced garlic and cook for another minute, until it smells fragrant and nutty.

Bloom the spices. Stir in the ground cumin, smoked paprika, and dried oregano. Cook for 30 seconds, stirring constantly. This step awakens the oils in the spices, filling the air with a warm, earthy scent. Immediately add the softened ancho chillies, the chopped chipotle chillies, and the adobo sauce.

Build the sauce. Pour in the chopped tomatoes and beef stock, using a wooden spoon to scrape up any browned bits stuck to the bottom of the pot—this is where so much flavour hides. Add the apple cider vinegar and brown sugar, then season with a generous pinch of salt and black pepper. Stir everything together; the sauce will look a deep, brick-red colour.

Braise the beef. Return the browned beef to the pot, along with any juices that have collected on the plate. Bring the liquid to a gentle simmer—you should see small bubbles breaking the surface, not a rolling boil. Cover the pot with a tight-fitting lid, then reduce the heat to low. Let it cook for 1 hour and 45 minutes to 2 hours, or until the beef is fork-tender and pulls apart with almost no resistance. The sauce will have thickened and darkened, clinging to the meat.

Shred the beef. Once the beef is tender, use two forks to shred it directly in the pot. You'll see the long, beautiful fibres separate easily. Stir the shredded beef into the rich, glossy sauce. Taste and adjust the seasoning with more salt or a squeeze of lime juice if it needs a little brightness.

Warm the tortillas and serve. While the beef rests, warm your tortillas. You can do this by dry-frying them in a hot pan for about 20 seconds per side, until they blister and smell toasty. Spoon the spicy beef into the warm tortillas and top with fresh coriander, diced onion, crumbled cheese, and a squeeze of lime. Serve immediately.