Boil potatoes for 10 minutes. Drain, collect the liquid and reheat. Add the peas and bring the water to the boil. Pour off immediately, measure out 150 ml of water.
Heat the oil in a pan and fry the onion, garlic and chopped ginger for 5 minutes until brown. Add the curry powder, tomato paste, the saved water, potatoes and peas. Cook for another five minutes and serve with chopped coriander leaves.