Pick the fenugreek leaves, keeping only the leaves and the very thin stems. Wash them in several changes of water, chop roughly, sprinkle with 1/2 tsp of the salt and leave for 10 minutes. Then squeeze them firmly in your hands to remove the bitter water.

Peel the potatoes and cut them into 2 cm cubes. Slice the onion; chop the garlic, ginger and green chilli.

Heat the oil in a large frying pan or wok over medium heat. Add the cumin seeds and let them sizzle for 30 seconds, then add the onion and cook until golden, about 5 minutes.

Add the garlic, ginger and chilli, then the turmeric, coriander and Kashmiri chilli. Stir for 30 seconds without letting the spices burn.

Add the potatoes and the rest of the salt, stir well to coat them in the spices, cover and cook for 12 to 15 minutes over medium-low heat, stirring now and then. Add 2 tbsp of water if they stick.

When the potatoes are almost tender, add the squeezed fenugreek leaves, stir and cook uncovered for 5 to 7 minutes, until the leaves are soft and the potatoes golden. If using kasuri methi, crush it between your palms and add it only 2 minutes before the end.

Off the heat, sprinkle with garam masala and add a squeeze of lemon juice. Serve hot.