Fry the onion over a medium to high heat for about five minutes until they soften.
Chuck in the garlic, ginger, and chilli. Cook for a further minute.
Add in the curry powder, cumin, coriander, and cinnamon.
Pour in the chopped tomatoes, coconut milk and add the tomato purée.
Add in the diced beef, stir well then cover with a lid and leave to simmer over a low-medium heat for about 2 hours, or until the beef is tender.
Add in the potatoes and cook for a further 30 minutes.
Season to taste, then add the chopped coriander. Dish it up with basmati rice and enjoy.