Preheat the oven to 160°C.

Heat half the olive oil in a heavy-based casserole pan over medium-high heat. Season the beef cheeks with salt and pepper and sear for 1–2 minutes on each side until browned. Remove from the pan. Add another tablespoon of oil, then add the onion and garlic and season with salt. Turn the heat down to medium and cook, stirring regularly, for 6-8 minutes until softened and lightly caramelised. Add the spices and oregano and cook for a further 1 minute before adding the chipotle and adobo sauce. Stir in the tomato and cook for 5 minutes until it breaks down.

Return the beef cheeks to the pan and 500 ml (2 cups) of water. Cover with the lid. Transfer to the oven and cook for 2–2 1/2 hours until the beef cheeks are tender. If they don’t fall apart easily, cook a little longer.

Meanwhile, place the sliced onion in a bowl with vinegar, sugar and a pinch of salt. Squash with your fingers and let macerate.

Remove beef from sauce and shred the beef cheeks with two forks before returning them to the sauce.

Heat a pan over medium heat and heat the tortilla for a minute on each side.

Serve the beef cheek with a dollop of yoghurt or sour cream, pickled onions, avocado and warm tortillas.