Soak rice, moong dal and methi seeds in water for 3-4 hours. Drain water and keep aside.
In a mixer jar, take drained rice mixture, grated coconut, jaggery and cardamom. Make a smooth batter by adding very little water. Take care not to add too much water at once. We don't want the batter to be runny.
Transfer eriappa batter into a container. If you are adding chiroti rava for some extra crispiness. Add at this stage and mix so that no lumps are formed.
The consistency of the final batter should be little thick like idli batter. If it's more watery it will drink more oil ...so take care.
Heat a heavy bottom Kadai /pan with enough oil for deep frying. When oil is hot enough, pour a ladle full of batter directly into the hot oil. Move the ladle in circular fashion just above the oil level while pouring.
Fry both sides of yelappa till brown in colour and crisp. Keep the flame on medium-low. Once it's done just squeeze the extra oil by pressing it using two slotted ladles and drain over kitchen paper.
Repeat the same process with the rest of the batter.
Yelappa is ready to serve.
Notes
Adding moong dal and methi gives soft texture and addition of fine rava makes crispy yeriappa
Grind adding small amounts of water at a time to make a smooth batter of a consistency slightly thicker than dosa batter.
The batter should not be thin. else it will be drink oil.
No need to ferment the batter. make it fresh for the best result.
Don't keep the flame on high while frying it will make yeriappa brown soon and the centre will be uncooked.