Devein the prawns by cutting through the shells, along the top of the back with a pair of sharp scissors. Lift out the vein with the tip of the scissors and pull to remove. This method keeps the shells on so that the prawns retain their delicious juices, but also allows the marinade to penetrate the flesh. Put
the prawns into a bowl.
Combine the ingredients for the marinade and pour over the prawns. Leave to marinate for 15 minutes. Meanwhile heat the oven to 230°C/gas 8.
Spread the prawns out on a large roasting tray greased with butter, and then dot the butter all over. Halve the chillies and scatter over, along with the curry leaves. Roast for about 10 minutes, or until the prawns are just cooked.
Meanwhile, dry-toast the desiccated coconut in a pan over a medium heat, stirring often until golden brown and fragrant. Remove the tray from the oven and stir in half the toasted coconut (kerisik). The toasted coconut will absorb the juices from the prawns and is one of the best bits of this dish.
Let the prawns rest a little, until cool enough to touch. Scatter the remaining kerisik over and stir though. Serve straight from the tray and let everybody dig in with their hands