In a mixing bowl, add 1 cup yellow moong dal and ½ cup poha. Wash them well.
Add 2 cups buttermilk (or as required) and soak the moong dal for 4 hours.
Moong dal is now soaked properly.
Add the soaked moong dal into a mixer jar. Add 3 green chillies, 1 inch ginger, 4 garlic cloves, ½ cup coriander leaves, and ½ cup water. Grind into a smooth paste.
Transfer the ground paste into a mixing bowl. Add ¼ tsp turmeric powder, salt to taste, and ½ cup rava. Mix well and whisk the batter for 2 minutes until it becomes light and fluffy.
Cover and let it rest for 10 minutes.
The batter is ready. The consistency should be medium thick and ribbon-like when poured. If it is too thick, add water to adjust.
In a tadka pan, heat 2 tbsp oil. Add 1 tsp mustard seeds, ½ tsp cumin seeds, 1 tsp chana dal, and some curry leaves. Sauté briefly.
Add the tempering to the batter and mix well.
Now add 1 tsp Eno and 1 tbsp lemon juice. Mix well; the batter will become frothy.
Grease the idli stand and fill each cavity with the batter.
Preheat the steamer and steam the idlis for 12–15 minutes on high flame.
Finally, serve hot moong dal idlis with peanut-coconut chutney and sambar.