Clean crab and keep it ready. Crab should be cooked immediately after cleaning and should not not be kept as such for a long time.
Grind ½ cup coconut, 1 tbsp whole pepper, 1 green chilli, 1" ginger, ½ tsp turmeric powder, 1 tbsp All purpose chilli powder (Kulambu milagai powder) to a slight coarse paste by adding enough water. In a pan add oil, when hot enough add chopped small onion, curry leaves and saute.
When onion is done, add crab, salt and turmeric powder.
Cook for about 10 min till water comes out of crab and drains.
Add grinded mix
and 2 cups of water
Let it cook covered for 30 min, making sure to stir in between.
After 30 min, the water would have drained off and masala would have been thicker.
Tasty crab roast is ready. Goes good with rice or chapathi or dosa.