Dry roast the rawa on low heat till it is light brown or till aroma wafts into the air. Keep it aside. Let it cool for atleast 20 minutes.
To make the watermelon rind puree – cut the watermelon into pieces. Cut the red watermelon and keep it aside. We only need the white part from rind. First chop the white part using the Hamilton Beach Hand Blender. Then make puree using the Hand blender’s blending wand.
You can make puree of the entire rind too, but the cake will be slightly bitter. I tried in both the ways and result was delicious in both cases.
Mix all the other ingredients one by one. First add the roasted semolina to the watermelon rind puree. Then add grated coconut and jaggery. Add all the other ingredients except baking powder and mix well. Keep this aside for 30 minutes. After 30 minutes add baking powder and mix again.
Prepare the baking pan by coating it with homemade ghee and flour. Apply the oil all over the pan and sprinkle flour on it. Spread it around. Pour the mixed cake batter in the prepared baking pan.
Pre-heat the oven in convection mode for 5 minutes at 205 C. For this, first rotate the timer past 40 and then rotate and come to 5 minutes again.
Keep the prepared baking pan with the cake mixture into the hot oven carefully and bake for 40 minutes.