in a large bowl, add 1 cup of roasted rava. using rava without roasting makes your idli slightly sticky.
to that add 1 cup of curd or yoghurt. it is best to use slightly sour curd. however it is not compulsory.
add ¼ cup of water and mix it well.
bring the batter to idli batter consistency by adding water if required
keep the batter to soak for 30 minutes.
after 30 minutes add ½ tsp of baking soda and give a stir. you can now see the batter turning slightly frothy. do not mix more.
grease the idli plates and switch on the steamer with enough water.
pour 1 tbsp of idli batter into each impression
place the flattened potato stuffing
gently press the aloo stuffing.
pour again 1 tbsp idli batter to cover the filling.
stack up all the idli plates and steam for 10-12 mins. rest it for another 3-4 mins.
unmould the idli plate and serve hot with chutney.