Heat the oil in a frying pan over a medium heat and cook the onion for 5-8 mins until light golden. Stir in the chilli, garlic and ginger, and fry for another minute before adding the spices. Tip in the cherry tomatoes, swirl the can out with a splash of water and stir that into the pan as well.

Simmer for 5 mins until the tomatoes burst and the sauce thickens. Stir in the tamarind and prawns, and simmer for 2-3 mins until the prawns are cooked. Serve the curry on top of the rice, with the coriander scattered over.