To the batter, add 1 tsp coarse salt. Mix batter thoroughly with your clean hands or a large spoon. Cover bowl with plastic wrap or a tight fitting lid. Leave in a warm place until it ferments. You will see bubbles on top of the batter when fermented. Batter will also have risen. Mix batter and add salt to taste. Batter is now ready to make idlis. If you want to make dosa, place some of this thick batter into another bowl and add enough water to make a thin batter.