Idlies are a staple breakfast item in our community,In fact  in every South Indian home for that matter irrespective of the caste he belongs to.Idly making is an art and comes by practice and trial and error methods.Though I am not an expert, I have by now fairly understood the points to be kept in mind and am able to make pretty much soft idlies . Earlier idlies used to be made by grinding  manually on a  stone grinder called ‘ragdo’ and every household had them  ,but now  a days its very rare.Now we all use wet grinder for grinding the batter. Also Idli rava was not available as it is available now and rice was soaked and ground and added to the batter.But when I started cooking Idli rava was available and my amma recommended  to me the same and hence I have always used idli rava for making idlies and today sharing with all of you too.I personally feel that idlies using idli rava turn out soft without using ingredients like poha or cooked rice while grinding.
                                               Please read the “NOTES” given at the end patiently and carefully to get the desired results.I have tried explaining in a detailed manner keeping in mind the simplest points.Hope this will help whoever wants to try.

  Ingredient:

1. Whole urad  – 2 cups
2. Idli rava  – 5 – 5 1/2 cups 
3. Salt to taste
4. Water for grinding

Batter mixed with idli rava and ready for fermentation

Recipe of Chutney:-
       Roast 1-2 green chillies or red chillies with a drop of oil.,just before taking them add a small piece of hing(the gum or wax variety) and fry.When cool grind with 1/4 cup coconut,marble sized tamarind and salt using water as required.season with mustard and curry leaves.
Notes:-

1. The fermentation of batter largely depends on the weather so grinding accordingly is very important.In extreme summers like in month of April and May I grind it in the evening after 6 and leave the batter for fermenting,If in any case you grind the batter early refrigerate and remove at night…when it comes to room temperature add the rava and leave for fermenting.
2. In winters I grind it at noon around 2 and leave it at room temperature only..at night mix rava and again leave it for fermenting.Also be careful while adding rava in winters,i have observed that batter sometimes holds less rava in winters than in summers.
3. In situations where it is neither hot or cold grind it around 4 in the evening and leave it.At night add rava and again ferment.
4. Now a days all the super markets and grocery/kirana stores have good quality and super fine idli rava which doesnt require soaking or grinding..if you feel your rava is bit large soak for some half an hour and just before taking out grind it for few minutes..though i have never done it as i always get fine rava and love a bit grainy texture to idlies.Grinding fine rava will make idlies sticky .
5. My amma and a senior and experienced friend in a food group suggests to place the cooker or steamer to heat and then fill the trays or moulds so that by the time we place the trays the water is heated .
6. If using urad dal use  double the quantity of idli rava.i.e for 1 cup of urad dal ideal ratio would be 2 cups of idli rava.Depending upon how the batter turned out..if the urad dal yields good amount of batter can add 1/4 cup more of rava or if you feel can decrease little less than 1/4 cup from 2 cups i.e add little less than 2 cups. As I have used whole urad I have used more of idli rava as I have found that whole urad yields large amount of batter(This was done by observing and trial and error method) .
7. If grinding in mixer grind in intervals adding water in between slowly so that the motor is not heated too much.My friends in food group say that the soaked urad dal or urad can be kept in fridge for an hour or ice cold water can be used to grind if using mixer.
8. Most importantly the batter depends on the quality of urad dal or urad used,the way we grind and also the time and weather …so we need to use our sixth sense while adding rava …which will come by experience and trial and error method.
9. If at all you have doubt regarding the addition of rava the next morning or you feel the batter has increased in volume too much…pour the batter in a small mould and steam and see how it turns …this will take hardly 4-5 minutes.If the idlies fall flat you need to add more rava.Soak around 1/2 to 1 cup rava for some 15-20 minutes and add to the batter and then proceed.Your idlies will turn perfect.
10. If you have added more rava then the idlies will turn hard and this cant be reversed so add carefully.  
11. I had to prepare the Idlies in large quantity so I have used 2 cups … for a small family of 3-4 persons 1 cup of whole urad will be sufficient..in that case add 3 to 31/2 cups of idli rava.
12. Always remember to add water in intervals and never at beginning ..this is applicable to both… grinding in mixie or wet grinder.