Bengali prawns with mustard and coconut

• Place the prawns into a large bowl. Mix the turmeric and Kashmiri chilli then sprinkle over the prawns. Toss to ensure the prawns are covered evenly. Cover and refrigerate for one hour.
• Roast the besan in a small pan until it turns golden brown. Set aside and allow to cool.
• Once besan has cooled, blend the mustard powder, besan and a splash of water to a paste in a small bowl. Set aside.
• Heat the mustard oil in a kadai or wok over medium heat until smoking. Remove from the heat when you have a clear, translucent oil. Set aside to cool for two minutes.
• Add the mustard seeds to the oil, return the pan to the stove and cook until the seeds start to sizzle.
• Add the sliced onion and sprinkle with salt. Stir well and fry for eight minutes, or until softened.
• Add the green chillies and fry for five minutes until chillies have softened and the onion is starting to colour.
• Add the garlic, ginger, and curry leaves. Cook for two minutes or until the raw garlic aroma has gone.
• Add the reserved mustard paste and grated coconut. Stir well to combine. Fry the mixture for three minutes, then add ½ cup water and continue cooking for another five minutes, or until the volume of liquid has reduced and the sauce is very thick.
• Add the prawns and cook, stirring or tossing until prawns are cooked. They need to become pink and curl; this takes only three minutes or so.

to serve

• Remove the prawns from the heat, sprinkle with the coriander and serve.