To prepare the Ellu Poornam, wash and rinse the black sesame seeds in enough water. Drain water completely and spread them on a cloth to dry for 15-20 mins. Dry roast them in a thick bottomed pan for 5-7 mins on low flame.
Once warm, grind them into a coarse powder.
Add it back to the pan along with jaggery powder.
Cook on low flame until the jaggery and sesame seeds powder are well combined for about 4 mins. You can remove it at this stage and use as dry stuffing too.
By now, jaggery should start melting. If it doesn’t, add 1 tbsp of water and quickly stir the mixture. It will be lumpy.
Cook for a minute or two, jaggery should completely melt and the mixture should leave the sides of the pan. Remove from heat and transfer it to a plate, let it cool down.
Meanwhile bring water to boil in a pan. Add a pinch of salt and 1/2 tsp sesame oil.
As the water comes to a rolling boil, switch off the heat and add the rice flour.
Quickly stir it without any lumps. Add the remaining 1/2 tsp sesame oil on top and keep it covered for 5 mins.
Once it is warm enough to handle, knead it to form smooth & soft dough.
Make equal sized balls of the rice dough and ellu poornam.
To make the kozhukattai, take a ball of the rice dough. Grease your palm with gingelly oil and pat the rice dough as thin as possible. It should not easily break – that shows that the rice flour is cooked properly and there is enough moisture in the dough.
Place a ball of ellu poornam at the center.
Bring the edges of the rice dough towards the center and cover the ellu poornam.
Shape it into a ball or as modak.
Repeat this with rest of the dough and poornam.
To steam cook the kozhukattai, grease a steamer plate with few drops of sesame/gingelly oil. Place the prepared modaks on the steamer plate.
Steam cook for 7-8 mins. Switch off the heat and let them cool down for a couple of minutes before removing them.