Wash prawns/shrimps properly in water. Wash them 2-3 times if they were frozen so that any preservatives are removed.
Add salt, turmeric powder, chilli powder, chicken masala powder (or garam masala powder), and 1tbsp oil. Mix well so that the seasoning is evenly applied to all pieces.
When done with mixing, set aside the seasoned prawns for 15mins.
Cut 1 large onion and 1 large tomato.
Take a frying pan. Set on low flame. Heat the pan for 2mins. Then add 5tbsp of oil. Heat the oil for 3mins and add the onions. Keep sauting onions till they turn slightly brown and its edges soften.
Add the tomato pieces and mix well. Close the lid and let it cook for 2mins. When you open the lid, you should see a little water leaving the mixture. This is the natural water in the tomatoes.
Now add the prawns and stir to mix well. Close the lid and let it cook in low flame for 5mins. When you open the lid, you should see some more water, which comes from our prawns. Mix well again.
Add 50-100ml water depending on how wet you want the curry to be. In my pictures, I added about 100ml of water since it gives off nice gravy in the end. But do remember, the more water you add the more cooking time it takes.
Important! Once you add water and mix well, taste the water with a spoon and make sure the spice levels suit your taste. Now close lid and let it cook for 20mins (for 100ml water added). Every 5mins or so, open the lid, drain the water droplets on the lid inner surface away, stir the curry and close the lid back.
Keep repeating till the gravy reaches the thickness level you prefer. I cooked for 20mins where I had added 100ml of water. Your curry is ready! Serve hot.