Boil the potatoes in their skins until cooked. Drain. Once they’ve cooled, slip off their skins and grate coarsely.
Heat the oil in a pan, add the mustard and fennel seeds. Once they begin to crackle add the curry leaves, onion and turmeric. Cook until the onion is soft and translucent.
Add the ginger, garlic and fresh chillies. Sauté for about a minute then add the chilli powder. Stir together and then add the crab meat. Stir-fry until all the moisture has been absorbed. Add some salt and remove from the heat.
Transfer the mixture into a bowl and add the potatoes, the lime juice and zest, the chives and the coriander. Combine well and season to taste. Allow to cool.
Put the flour, eggs and breadcrumbs into three separate bowls. Shape the crab mixture into eight cakes. Lightly dust each in flour, then dip into the egg and finally coat with the breadcrumbs.
Heat the oil for frying in a pan. Add the cakes in batches and fry for about 2 minutes on each side or until golden brown all over. Drain on kitchen paper and serve with coriander and yoghurt dip.
For the coriander and yoghurt dip, put all the ingredients into a food processor and blitz until smooth and runny. Place into a bowl and adjust the seasoning. Refrigerate until required.