Wash and soak urad dal(with methi dana) and jowar seeds in a bowl with enough amount of water overnight or 4-6 hours
Blend sorghum with urad dal ,water and salt in a mixer (this takes around 40-50 seconds in a vitamix blender) once its nearly done. You may blend in 2 or more batches depending on the capacity of the mixer.To make idli. Keep the batter aside to ferment overnight in a warm place.(refer notes)
To make jowar idlis
Grease idli pans with butter/ghee/oil, pour a ladle of batter in the pan
move the idli rack into a steamer and steam for atleast 12-15 minutes.
Jowar dosa
You can use fresh batter that is not fermented or use the fermented batter.In a bowl take some amount of batter and add some water to get a thin pouring consistency.You may add salt if required.
Once its medium hot,add a big ladle of batter and spread it evenly
Add little oil on the edges.Let it cook for few minutes ,until rawness dissapear
Optionally flip it and cook on the other side for few mins.Using a spatula,take out the dosa.
Sprinkle some water and repeat for the remaining fermented batter.