Peel and cut the potatoes into large chunks.
Pick and chop the coriander.
Peel and chop the garlic cloves and the ginger. Set aside.
Peel and dice the onion. Heat a saucepan and add the oil. Fry the onions until golden brown with the salt, dark mustard seeds and curry leaves.
Add the potatoes, garlic and ginger, and cook for a further 2 minutes. Add the rest of the ingredients and cook for 30 seconds.
Add cold water to half cover the potatoes. Bring to boil and simmer until the potatoes are cooked and all the liquid has been absorbed. The dish should be slightly moist but dry.
Stir in the frozen peas, and heat through.
Add a squeeze of lemon juice, if necessary, and stir in the chopped coriander. Check the seasoning and adjust if necessary.
Serve while hot with naan bread or as an accompaniment to a curry.
«Curry leaves are easily found in Asian shops, and freeze very well. If you cannot find them, leave them out of the recipe, or substitute with a bay leaf: they do not taste the same, but both herb are used to round off flavours in a dish.»