In a bowl, add gram flour, salt, turmeric powder, red chilli powder, coriander powder, hing, ajwain, green chilli paste, ginger paste, garam masala, white sesame seeds, tamarind water and jaggery.
Add required water to make medium thick consistency of batter.
whisk batter into one direction for 2-3 mintes.
Then add hot oil and mix well. Keep it aside.
Preparing patra roll
Clean colocasia leaves by trimming its thick stalks and veins from bottom side using a knife. Trim all the leaves in this way and keep aside.
Take first big size leaf and spread gram flour batter evenly on the patra leaf keeping leaf upside down.
Place another leaf over it and spread a layer of batter over it.
Similarly prepare 3rd and 4th layer. you can make up to 4 layers.
To make a roll fold the bottom sides of leaves. On each fold spread some batter over it. Fold from the sides and roll it tightly.
Steaming patra
Now in a deep bottom vessel (big patili) add 3-4 cup of water and bring to boil. When water comes to boil, put this plate with hole on it and grease it.
Place patra roll on it and cover it with big vessel. Then steam patra for 15-20 minutes at medium-high flame.
The best way to check that they are cooked or not is to insert a knife in the middle. If it comes clear, Patra is done.
Switch off the flame and let it rest.
Cut them into pieces.
Patra with tempering
In a pan, add oil, mustard seeds, white sesame seeds, hing, curry leaves and chopped green chilli. Sauté for a minute.
Add turmeric powder and Mix well.
Then add 3 tbsp water and bring it to boil.
Add patra into tempering and coat with it.
Then lower the flame and simmer for 5 minutes.
Switch off the flame and add lemon juice and chopped coriander.
Keep covered for 2-3 minutes and then serve.
Preparing crispy patra
In a bowl, add gram flour, salt and turmeric powder. Add water and make a thin batter.
Add patra roll in it and coat with with batter.
Now, In a Pan heat oil and fry patra on it.
Once it is brown and crispy turn it over and cook on other side as well.
Serve crispy patra is ready to eat.
Notes
Tamarind water and jaggery mixture gives khatta-meetha taste to patra.
You can use curd or buttermilk instead of tamarind pulp
Whisk batter in one direction so air particles incorporate into it and the batter becomes light and fluffy.
The consistency of the batter should be medium thick and pouring, so it will easily spread to leaves.
Spread a thin and even layer of batter on the leaves.
Steam patra roll on high flame for 15 minutes. also If the knife comes out clean then Patra is properly cooked.
Cool down patra roll completely, do not cut it when it is slightly hot.