Pressure cook the jackfruit seeds and mash them lightly. Grind them into a thick smooth paste by adding some water and keep aside.
In a mixer grinder jar, add the soaked and drained rice, Urad Dal, soaked poha, methi seeds,grated coconut. Grind them using little water until smooth
Add the thick jackfruit seeds paste and grind once again until the batter has mixed well.
Remove the contents in a vessel. Cover and Allow it to ferment for 8 to 10 hours, preferably overnight.
After the batter has fermented, add salt and turmeric powder. Mix lightly. Add some water to adjust consistency and start preparing the dosas
Heat a griddle, add oil and lightly grease the pan.
Pour a ladle of this batter and gently spread, pour few drops of oil on the side and cover the dosa pan with a lid. Note - you should not spread the batter like regular dosa. It has to be thicker like a uttapam, only then you will get the spongy effect and the perforation.
Remove the dosa from the pan and serve immediately / store in a casserole until breakfast.