Step 1: Prepare the filling: In a heavy-bottomed pan, combine freshly grated coconut, grated jaggery, cardamom powder, and an optional pinch of salt. Cook over medium heat, stirring continuously, until jaggery melts and the mixture thickens, pulling away from the sides of the pan (about 8-10 minutes). Remove from heat and let cool completely.
Step 2: Prepare the batter: In a large bowl, whisk together rice flour, all-purpose flour (if using), sugar, and a pinch of salt. Gradually add coconut milk and water, whisking until a smooth, thin, lump-free batter is formed, similar to crepe consistency.
Step 3: Rest the batter: Cover the bowl and let the batter rest at room temperature for at least 30 minutes to allow the flours to hydrate.
Step 4: Cook the pancakes: Heat a non-stick griddle or tawa over medium heat. Lightly grease with oil or ghee and wipe off excess. Pour a ladleful of batter onto the hot griddle and quickly swirl to spread into a thin, even circle (6-8 inches).
Step 5: Stuff the pancakes: Cook for 1-2 minutes, until the edges curl and the surface is set (no need to flip). While still on the griddle, spoon a generous amount of the cooled coconut-jaggery filling onto one half of the pancake.
Step 6: Fold and serve: Gently fold the other half of the pancake over the filling to create a semi-circle, or roll it up. Press gently to seal. Transfer to a serving plate. Repeat with remaining batter and filling. Serve warm.