Heat the oil and add the Cardamom and onions. Sauté for 3-4 minutes.
Stir in the Ginger, Garlic Granules, Turmeric, Chilli Powder and 3 tsp of the Coriander Leaf. Add a little hot water, stir in the tomatoes and Cumin. Cover and cook over a low heat for 5-8 minutes, until the onions are brown.
Add the prawns and stir fry for 4-5 minutes.
Remove from the heat. Stir in the yoghurt and Garam Masala and serve immediately, sprinkled with the remaining Coriander Leaf.