Wash the raw rice under running water until the water runs clear. Soak the washed rice in water for 4-6 hours. At the same time add 2 tsp of sugar to the coconut water and refrigerate.
If using thick poha, wash it and soak for 2 hours. If using thin poha, no need to soak it.
Drain the water from soaked rice and poha. Add soaked rice, poha, coconut and cooked rice to the grinder. Add 1/2 cup coconut water and grind everything to a smooth paste (refer notes).
Transfer the batter to a medium -large size bowl.
The batter should be pourable but thick. If the batter is too thick add the remaining coconut water and mix well. I used around 3/4 cup of coconut water.
Cover the bowl and leave the batter to rise for 8 - 10 hours or overnight.
Once the batter is ready, add salt. Do a taste test and add more salt/sugar to suit your requirements. Also, if the batter becomes too thick after rising, add little water to loosen it.
Heat a nonstick pan and pour a ladleful of batter. Do not spread the batter since it will spread by itself. Cook on low-medium flame for two mins or until the edges are set. Flip the appam and cook the other side also. Serve hot with your fav side dish.
Notes
I used the biggest jar of the mixie and grind everything in one go. However, if your mixer jar is not big, I suggest you grind it in two batches. If your mixer tends to get too hot while grinding, you can refrigerate the soaked rice and poha. I got 10 standard size appams from the above quantity. I've noticed that the risen batter stays good for only a day since there is no yeast in it. You can make Appams in one go, refrigerate the leftover (if there is any) and reheat it in a steamer.