Take powdered oats, sooji and salt in a large bowl. Stir well so everything combined well.

Now add yogurt. Again mix well. Keep it aside for 15 minutes.

Take cumin seeds and black peppercorns in mortar and pestle.

Crush them together into coarse powder. You can use dry spice grinder or coffee grinder.

Heat the oil in a pan for tempering on medium heat.

Once hot add mustard seeds. Let them pop.

Then add cumin seeds. Let them sizzle a bit.

Now add cashew nuts. Stirring constantly, saute till they are light brown in color.

Now add chopped green chilies, ginger paste and curry leaves. Saute for a minute.

Now add prepared cumin-pepper powder. Immediately stir and turn off the stove.

Add this tempering to the idli batter.

Mix with spatula till everything is incorporated well.

Prepare the steamee. Add a glass full or two of water in a steamer. let it come to a simmer on medium heat.

Also grease the idli moulds using little oil.

Sooji may have soaked up moisture and batter may have become too thick. So add ½ cup to ¾ cups of water.

Mix well and make right idli batter consistency.

At the time of steaming, add eno fruit salt.

Add eno only to the portion of batter which you are going to steam right away. As this is big batch, I need to steam them in two batches.

So I have divided the batter into two bowls and added eno to the first batch and steamed.

drizzle about 2 teaspoons of water on top. It starts to fizz up.

Immediately mix the batter.

Divide them into idli moulds.

Steam for about 12-15 minutes or till a toothpick inserted in idli comes out clean.

Remove the idli stand from steamer. Let it stand for few minutes.

Then using spoon (dipped in hot water), remove the idli from the moulds.

Repeat the same for second batch