Wash and soak rice and black gram separately for 3 hours. Grind them together into a pouring consistency. Cover and keep aside overnight.
Mix all the ingredients except oil in the fermented batter.
To prepare this you need ponganalu pan. Place the pan on stove and keep it on medium flame and put oil in each impression.
When the skillet is hot, take small ladle full of batter and fill the impressions with batter.
Cover and cook for 5 minutes on low flame till brown spots appear at the edges.
Gently flip the ponganalu with a spoon and cook for some more time.
Repeat the process till the batter is done.
Serve hot with any chutney or tomato sauce.