Soak the Rice: Begin by soaking raw rice in water for about two hours.
Prepare the Jaggery Syrup: Take jaggery and dissolve it in a small amount of water. Strain the syrup to remove any impurities.
Grind the Ingredients: In a mixie jar, add the soaked rice, jaggery syrup, and cardamom. Grind everything into a smooth paste. Next, add ripe banana and grind again until you achieve a smooth batter. If needed, add a little water to reach an idli batter consistency.
Prepare the Coconut: Thinly slice coconut pieces and fry them in ghee or coconut oil until golden. Mix them into the batter.
Ferment the Batter: Let the batter rest for 3 to 4 hours, or preferably overnight, to allow it to ferment. This step is key to making soft, flavorful unniyappam.
Cook the Unniyappam: Heat the appa kaaral (special pan) on the stove and add a mixture of ghee and coconut oil into each mould. Once the oil is hot, spoon the batter into each mould. Cook on low to medium heat for even cooking.
Flip and Cook: Gently turn the unniyappam with a wooden skewer or stick to cook the other side. Continue cooking until they are golden brown.
Serve: Serve the unniyappam hot or cold, as desired.