Shell, devein and wash prawns with salt water. Rub prawns with 2 teaspoons ground turmeric and 1 teaspoon salt. Set aside for 30 minutes.
2
Skin and quarter large potatoes. Halve small ones. Rub with 1/2 teaspoon salt and 1 teaspoon ground turmeric. Fry in 2 ounces oil over medium heat until golden brown. Remove to a dish.
3
In the same hot oil, fry cumin, cinnamon and cardamom for 1 minute, then add sliced onions and stir-fry for a further 5 minutes. Add prawns, ground chili, ground coriander, ground onions, ginger juice, yogurt, sugar and salt to taste.Stir to mix well.
4
Add 3/4 pint boiling water and potatoes and cook until potatoes are tender and the gravy is very thick. Now add sliced tomatoes and remove from heat.Serve with bread or rice. Serves 8.