Wash and drain the pawns; wipe with a paper towel / clean cloth to ensure they are completely dry. Marinate them with a little salt and turmeric powder. The prawns do not need to marinate any longer than 10 mins.
Roast the fenugreek, mustard and cumin seeds, dried red chilies and coriander seeds / powder on a low flame for 3 – 4 mins. They should change colour and give off a nutty roasted aroma1. Cool and grind to a fine powder2.
Heat a couple of tbs of coconut oil in the same pan that was used to roast the spices; sauté ginger and garlic for about a min. Next, add finely chopped red onion and sauté till soft and translucent.
Add finely chopped tomatoes, salt and slit green chilies to the pan; stir well, cover and allow to simmer until the tomatoes soften. Add the ground spice mix to the tomatoes, combine and simmer once again for about 3 - 4 mins until you see the oil separate from the cooked mixture. It should be a fairly dry paste at this point3.
Next, add the softened tamarind pulp and water to the pan. Be careful to remove the seeds and fibers from the pulp first. Simmer for a minute until you have a wet mix once again4. Taste test, and season with more salt (if required) at this point. The salt and sour taste from the tamarind need to balance out.
Add the prawns to the masala, stir, cover and allow to cook on low heat for 4 – 5 mins. You know the prawns are cooked through, when they change colour to a light pink and go completely opaque. Its important to cook them on a very low flame so that they remain soft; if overcooked, they could end up being rubbery in texture5.
Turn off the heat and stir in a third of a cup of grated coconut. This will thicken the masala instantly5.
The tempering6: this all-important step is a flavor booster! Heat 2 tsp of coconut oil in a small pan (a tadka pan, if you have one). When hot add the curry leaves and allow them to crackle and crisp up. Turn off the heat; pour the tempered curry leaves over the prawns and immediately cover with a lid so that the aroma of the curry leaves seeps into the dish. Keep covered for about 2 mins.
The last and final step, is to garnish with chopped coriander leaves and julienned ginger. These finishing touches add a freshness that contrast the heavy spice really well!