Wash the rice rava. Run the pulp through a sieve. Mix the rice rava and soda with the pulp and keep aside for 1 hour. Later mix this well with jaggery, salt, and cardamom. Pass the banana leaves over a flame for a few seconds on both sides to make them more pliable. Onto each leaf pour 4 Tablespoons of the Rava mixture and garnish with coconut bits. Fold the banana leaf over the mixture and fasten with toothpicks. Likewise with the remaining pieces of banana leaf. Pile up the folded leaf strips filled with Rava mixture in a shallow vessel and steam for 30-40 minutes. Serve with the banana leaf. Apply a little ghee before eating.