To make the tamarind mixture, place the tamarind paste, chilli powder, cumin and turmeric in a small bowl with the measured water and stir to mix well.
Heat the oil in a large nonstick wok or frying pan over a medium heat. Add the garlic and prawns and stir-fry for 2–3 minutes.
Stir in the ginger, chilli, measured water and tamarind mixture. Bring to the boil, reduce the heat and simmer for 2 minutes, then stir in the coconut cream.
Gently simmer the mixture for 2–3 minutes, stirring constantly, until the prawns turn pink and are just cooked through.
Remove from the heat, season with salt and stir in the fresh coriander. Serve immediately with steamed basmati rice and pappadoms and garnished with lime wedges.