1. Mix the prawns well with lemon juice. Keep aside for 10 minutes. Wash the prawns under running water. Drain and keep aside.

2. Heat the ghee in a wok (kadhai); add tomatoes, stir and add garlic, ginger, and green chillies. Saute until the tomatoes turn soft.

3. Add 1/2 cup water and bring the mixture to the boil. Mix in red chilli powder, turmeric powder, and cumin powder. Add salt and prawns. Cook for 8 - 10 minutes until the water evaporates and the prawns are done.

4. Serve hot.