This is the traditional method of preparing Appam from scratch. The process requires a total of 6-8 hrs of fermentation.
Rice Prep: Wash n Soak idli rice for 4-5 hrs.
Yeast Prep: Prepare yeast mix by mixing ¼ cup warm water with 1 tsp sugar. Add yeast and allow it to sit for 15 minutes. It will froth by this time. Using a spoon, mix it well. Keep aside.
Making Batter: In a blender, grind the soaked idli rice with grated coconut, cooked rice, 2-3 tbsp sugar, and either of water / coconut milk / coconut water (in batches), till it forms a smooth batter. Make sure your batter is not too runny, it should be slightly thick with a pourable consistency.
Fermentation: Allow it to sit at room temperature for at least 8 hrs or overnight, so that it ferments. Use a long-bottomed pan / bowl (preferably glass) as the batter will double in quanitity, ensure to cover the bowl.
Make Appams: To prepare the appams, heat an appam pan (or regular pan if you don’t have one). Once hot, season the pan with a little oil and pour a ladle full of batter on to the center of the pan. Swirl the pan so that a thin coat of the batter covers the edge, forming a properly shaped appam (thick in the center and thinning outwards). Cover the pan with a lid and cook on medium flame. Once the edges turn golden brown and the center cooked, remove it to a plate.
Taste your first appam and add more sugar to the batter if needed. Appams taste best when sweet.
Pro-tip: If you are living in a cold place during peak winter times, keep your batter inside an oven for the proper fermentation process.