Put the rice in about 1/8 l boiling salted water. Cover and let it swell for about 20 minutes
Peel and finely chop the onion. Knead with tartar, mineral water, salt, pepper and cumin. Form 4-5 balls from the chopped mass. Fry in a coated pan in hot oil all around for about 10 minutes
Cut the mango into fine strips. Mix yoghurt and starch until smooth
Remove the balls. Sweat curry and chili in hot frying fat. Deglaze with mango juice. Stir in yoghurt, bring to the boil and simmer gently stirring for about 1 minute. Add balls, mango and grated coconut to the sauce. Season to taste with salt and pepper. Serve with the rice