For the spice paste, toast the grated coconut in a dry frying pan over a medium heat for 3-4 minutes, or until lightly browned, then tip onto a plate and set aside to cool.
Return the pan to the heat and toast the dried chillies, coriander seeds, peppercorns and cloves for 2-3 minutes, or until lightly coloured and aromatic, then tip onto a plate and set aside to cool.
Transfer the toasted spices and coconut into a food processor with a few tablespoons of water (or coconut milk) and blend to a smooth paste. Set aside.
For the lobsters, heat two tablespoons of the vegetable oil in a wok and fry the onions and chilli for 5-6 minutes, or until coloured. Stir in the ginger and garlic paste and turmeric and fry for a further 2-3 minutes, then stir in the spice paste.
Add the tamarind pulp to the pan and simmer for 2-3 minutes, then pour in the coconut milk and simmer for another 8-10 minutes. Add the water to thin out the mixture slightly, then stir in the coriander leaves.
Heat the remaining vegetable oil in a non-stick frying pan and fry the lobster meat for 3-4 minutes, or until golden-brown all over. Add the butter to the pan and, when melted, spoon over the lobster to form a light glaze.
To serve, spoon some of the sauce into four shallow serving bowls and divide the lobster meat equally among them. Serve with a bowl of boiled rice or green salad.