Roast moong dal until golden in colour in medium flame.
Pressure cook with 1 cup water, upto 4 whistles in medium flame. Mash it once done.
Heat jaggery, with water just to immerse it.
Once dissolved, filter through a metal strainer and continue heating in a heavy bottomed pan.
Once the syrup is frothy, add mashed dal and mix well.
Add coconut, cardamom and keep cooking until the mixture thickens and becomes a mass.
For outer layer dough, boil water well until it bubbles.
Add it to the idiyappam flour in a mixing bowl, with sesame oil and salt (my flour had salt in it, so did not add).
Add hot boiling water little by little and mix with a ladle. Keep aside closed with lid.
Once warm enough to handle, add little more sesame oil and knead the dough smoothly.
Divide into equal sized balls. (12-14 ). Keep covered all the times.
By now the pooranam would have cooled down. Knead smoothly and roll into equal sized balls.
Make bowl shape with the dough.
Stuff with pooranam and cover the pooranam from all sides. Gather on top. Seal properly and hape to modaks.
Arrange in a greased steamer plate/ Idli plate (I used my idliyappam steamer).
Steam for 5-8 minutes or until the outer cover gets shiny.