Mix together the besan, dahi, salt, ginger, chilli paste, and citric acid or vinegar. Add enough water to make a paste of drooping consistency. Leave for about one hour (for best results) gets the steamer ready. Gently mix in soda and transfer immediately to the greased tin. Sprinkle the red chili powder, rai and kadhi patta. Place the steamer, cover the steamer tin. Steam for 20 min. add remove from vessel, garnish and serve hot.