Heat the oil in a saucepan. Add the chillis and fry for 1 minute.

Stir in the onions and fry until they are golden brown.

Add the beef cubes and salt. Fry for 10 to 15 minutes, or until they are deeply browned all over.

Stir in the tomatoes and cook for 10 minutes, or until most of the liquid has evaporated.

Combine the turmeric, cumin, coriander and 1 teaspoon of the garam masala. Beat in the yogurt. Stir this mixture into the mixture in the pan, reduce the heat to low and half-cover. Simmer for 1 1/2 hours.

Remove the lid from the pan and simmer the curry for a further 30 minutes, or until the liquid has evaporated leaving the meat covered in a thick gravy. If the curry becomes too dry too quickly, cover and continue cooking.

Transfer the mixture to a warmed serving dish and sprinkle over the remaining garam masala and the coriander leaves.

Serve at once.