Takes 25 min to make, 2½-3½ hours to cook
Mix the curry powder with the allspice and mace in a large bowl. Add the beef, season well and toss to coat. Heat a good layer of oil (about 3 tbsp) in a big frying pan and brown the beef all over in batches, adding more oil as necessary. Transfer the beef to a casserole after each batch.
Heat a little more oil in the pan if needed, then fry the onions and chillies for 10 minutes until they start to brown. Add the garlic and ginger and any leftover spices from coating the beef, cook for a minute more, then add to the casserole.
Add the coconut milk, tomatoes, thyme and enough water just to cover the meat. Bring to a gentle simmer and cook, partially covered, for 2-3 hours, stirring occasionally, until the meat is very tender. Add a splash or two of water if needed.
When the meat is tender, add the potatoes, taste and adjust the seasoning, then cook for another 20 minutes until the potatoes are tender. Take off the heat, skim any fat from the surface, then serve with rice and extra thyme sprinkled over.
