Mix spices except for Garam Masala in a small bowl. Opt to dry roast the mixed Indian spices before adding to prawns. Divide in half.
Season prawns with half of the mixed spices – Fenugreek Powder, Ginger Powder, Granulated Garlic and Curry Powder. Let it stand for at least 15 minutes. Pour lemon juice before pan frying (if using lemon juice).
Heat pan with oil. Pan fry shrimp by batch – 1 to 2 minutes on each side. Drain.
In the same pan, fry the shrimp heads to extract flavor. You may discard once it’s thoroughly cooked or enjoy them with gusto!
Using the same pan, sauté onions until translucent and fragrant.
Add tomatoes, sprinkle the remaining spices, add red chillies and Garam Masala. Mix well. Simmer on low heat for 5 to 8 minutes.
Add pan-fried prawns and pour coconut milk. Continue to simmer for about 5 to 10 minutes or until sauce thickens and prawns cooked thoroughly. Season with salt and ground black pepper to taste.
Garnish with fresh coriander leaves. Enjoy.