- Combine the marinade ingredients and mix. Add the prawns, cover and refrigerate for at least half an hour.
- Heat the oil on a medium flame. Add the diced onions and cook until starting to colour, about 10 minutes. Add the green chillies and garlic and mix for 5 minutes. Don’t let the garlic burn. Add the tomatoes and cook until soft and collapsed, about 10 minutes.
- Add the coriander, cumin, chilli powder and salt and mix through. Cook until the oil separates out. Add half a mug of water and mix. Cook until you get the desired consistency. Taste and adjust for salt and chilli levels. Use a hand blender to smooth out the masala.
- Add the raw prawns and heat until cooked through (5-10 mins). Take off the heat, mix through the fresh coriander, and add a generous squeeze of lemon juice.
- Serve with cumin rice or roti.