Soak urad dal and idli rava, separately, for 4~5 hours.
Drain the water from the urad dal and reserve about 2 cups of soaking water. Grind the lentils into soft and smooth paste by adding little water.*
Soak poha for 15~20 minutes and grind to a smooth paste. Add to the dal.
Squeeze excess water from idli rava. Add to the dal batter and mix well with hand.
Add cumin seeds and salt to the batter and mix well. It is time to make dibba rotti.
In a deep round or flat bottom pan, heat 1 tablespoon oil on medium heat, add about 1~1½ cups* of batter.
To evenly cook the inside, place a small spoon or a tiny plate in the batter and push it in. Cover and cook on medium-low flame for about 10~15 minutes or until the rotte is golden brown and crispy on the outside.
Once ready, it will move around the pan without sticking to the bottom. Check if the inside is cooked by using a knife and if it comes out clean, then it is ready to turn.
Turn the rotte over and cook on the other side for another 5~8 minutes.
Once done, turn off the heat and let it sit for a 5 minutes before removing from the pan. Repeat with the remaining batter.
Remove from the pan, cut into wedges and serve with chutney, sambhar or pachadi.