Wash rice for wrapping and soak in hot water for 8 hours. Drain and grind with salt and 2 cups water. Set aside.
Wash and scrub mussels well. With a sharp knife, scrape off the poisonous beards and filaments at the joints of the shell. Wash again.
Place mussels in a pan with water to cover and boil for 30 minutes. Drain mussels and prise open shells with the edge of a sharp knife. Rinse mussels in fresh water, drain well and cut into 2-3 pieces.
Mix mussels with coconut, onions, garlic ,curry leaves, chilli powder and salt.
Heat oil in a pan and sprinkle in mustard seeds. When they start sputtering, add mussels-coconut mixture and fry for 5 minutes, stirring occasionally.
Add scant ½ cup water and cook till dry. (If there is excess water wrap mixture in a thin muslin cloth to absorb it.)
Rub your hands with oil and pinch off lime-sized portions of rice paste. Flatten and place 2 tbsp of mussel-coconut mixture in the centre. Work wrapping around to cover filling completely and shape into a round dumpling.
Steam dumplings for 15 minutes.
Note: Discard any mussels that are not tightly shut.
Variation: Minced chicken, mutton, beef or crabmeat can be substituted for mussels.
