Clean and wash prawns. Drain water thoroughly, marinate with ½ tsp. ginger garlic paste, ¼ tsp. red chili powder, little salt and lemon juice. Set this aside till you prepare the rest.
Making royyala iguru
Heat a pan with oil, add cumin, and curry leaves and green chili. Sauté till the curry leaves turn crisp
Add onions, sprinkle salt and fry till they turn golden, reduce the flame to minimum (sim), continue to fry till they caramelize. Take care not to burn them.
Add ginger garlic paste and give a quick stir. Since the onions are already caramelized the ginger garlic can get burnt. Take care
Add the marinated prawns and fry for 2 to 3 mins
Add the rest of the red chili powder, turmeric and garam masala. Give a good stir and fry for a min
Sprinkle some water just enough to bring in some moisture for the prawns to get cooked. I used almost 90 ml water.
Cover and cook on a medium flame till they are completely cooked. I understand them to be cooked when they curl up and turn pink or orange. If there is more water left, you can evaporate by cooking further without a lid