Wash the rice and soak overnight. Drain and grind the rice finely with some of the toddy.
Finely grind the grated coconut.
Mix the rice and coconut paste with salt to taste and about 4 Tbsp (or more) sugar.
Add enough toddy to make a thick batter.
Cover and keep in a warm place for about 3 hours until batter doubles in quantity.
Pour batter into flat plates or idli moulds and steam for 20 minutes.
To check if the sannas are done, pierce with a knife.
If the knife comes out clean then the sannas are done.