Preheat a heavy bottomed large saucepan at medium heat. Add cumin seeds and dry roast for about 2 minutes or until aromatic and dark brown. Remove cumin seeds and set aside.

Pour vegetable oil into pan and increase heat to medium high. Toss in onions and cook for about 5 minutes or until golden brown. Add cayenne powder and cook for 30 seconds or until oil starts to separate from the onions. Add chopped garlic and ginger and cook for 30 seconds. Stir in cumin powder and cook for 2 minutes. Add stewing beef and season with salt and pepper. Cook, stirring regularly, for about 15 minutes until all of the meat has changed colour and has lightly browned. Toss in tomatoes, green chilli, toasted cumin and a quarter cup of water. Cover and simmer over low heat for 45 minutes or until tender. Occasionally give the meat a stir. Once the meat is tender, remove the cover and simmer until most of the liquid has reduced but still lightly coats the meat.

While the curry is simmering, bring a large pot of salted water to boil. Toss in one type of root vegetable and cook until tender. Remove with a slotted spoon and set aside. Repeat with other vegetables, if using.

When you are happy with the consistency and tenderness of the curry gently stir in the cooked vegetables. Check and adjust seasoning, if need be. Garnish with julienned ginger and roughly chopped coriander and serve immediately.