Boil 4 1/2 lb potatoes in their skins until half-cooked; skin and cut into 1 cm cubes.

Fry 4 dried, crushed red chillies and 2 tsp black mustard seeds in 5 1/2 floz oil or ghee until the seeds burst.

Add the potatoes and fry until golden brown. Stir-fry 50 g grated ginger in 50 ml oil or ghee, add 1 kg shredded cooked spinach, stir in 7 1/2 floz natural yogurt, cook for 5 minutes, then add the cooked potatoes and seasoning.

Serve sprinkled with chopped coriander leaves.