a small handful of fresh chopped coriander to garnish
Step by step
Heat half the oil in a large deep flameproof casserole dish and fry the diced beef in batches over a high heat until browned all over, adding the rest of the oil if needed. Remove the meat with a slotted spoon and set aside.
Add the onions to the casserole dish and fry over a medium heat for 5 minutes, adding the chopped chilli after 2 minutes. Stir in the massman paste and cook for 1-2 minutes. Return the beef to the casserole dish with the coconut milk and bring to the boil. Reduce the heat to a very gentle simmer and cover tightly and cook for 1 hour 30 minutes, stirring occasionally.
Uncover the casserole and add the potatoes to the dish. Cover and simmer for 45 minutes, or until the beef and potatoes are tender.
Stir in the lime juice and sugar and simmer, uncovered, for a further 15-20 minutes until the liquid has reduced slightly. Season to taste with salt and freshly ground black pepper.
Serve the curry garnished with chopped coriander, if liked and with boiled rice and lime wedges.