Choose pattarveli leaves that have dark purple stems, that are vibrant green (new leaves look deep purple which is ok too) and are tender as well as thin. Don't take the leaves with green stem (see pic 3).

Place a leaf on a flat surface and try to remove the stem of it using the knife held parallel to the leaf. Remove the main thick stem as much as possible as well as the small nerves attached to the stem. It is very important to remove them otherwise they hurt in the throat giving an itchy feeling. The hard stem also crack the leaf as we fold it. Prepare all the leaves similarly and wash them well. Put them on a tilted plate so the water drops out.

Take about 3/4 cup water (150 ml) in a bowl. Add tamerind and jaggery. Heat up and bring it to boil. Rest aside till the jaggery melts and tamerind gets tender. Sieve it while catching the water.

Combine all the ingredients for paste. Mix well and then add the jaggery-tamerind water. Add oil. Combine well.

The paste should be loose, but thick (ribbon consistency) like cake batter. Add more water if required. Add more chanaflour if it is too thin.

Pay a big leaf upside down on a flat surface. Apply this paste evenly all over the leaf. Do not apply too much or too little paste. Put another leaf on the top of it, upside down and pointing the other way round. Apply an even layer of paste on it. Similarly make total 5 layers of leaves on the top of each other, placing each in the opposite direction of the previous leaf.

Now fold inwards the two long sides of the leaves. Each fold should be not more than 3 fingers wide. The width will be lesser for smaller leaves. Now start rolling tightly from the top coming down. Apply a small amount of paste on each fold.

This is how the roll will look. Prepare such rolls using all the rest of the leaves.

Prepare a steamer with some water in a deep pan and a plates with holes in it. Put it on medium to low heat. Place the rolls in it. Cover and cook for about 30 min.

When ready, the rolls will turn darker in colour, will look tender and a knife will be easily pricked through. Cut the rolls into half to one cm thick discs. You can store them in a refrigerator if you are planning to use them on the next day. Bring them to room temperature before use.

At the time of use, combine coconut, ginger, garlic, green chillies and coriendar leaves in a nut chopper (also known as chilli cutter). Grate them all together. This way we'll get coarsely grated texture of them. That's exactly what we are looking for. Heat up oil in a pan. Crackle mustard seeds and sesame seeds. Add asafoetida powder and then patra (the discs make from the cooked rolls of leaves).

Add the paste (keep a little to garnish), lemon juice and sugar. Adjust other seasonings as per your taste. Combine everything very well. Remove from heat. Transfer them in a serving plate, garnish with the remaining paste. You can also grate some more coconut over them. Serve hot or at room temperature with tea.

Method : 2
Above method makes very well moistured and sift Patra. If you like crispy Patra, you can shallow fry them on a flat nonstick pan after crackling mustard and sesame seeds. Shallow fry till they are golden and crisp on both the sides. Crispy version of it makes patra a bit dry do they are not so favourite of mine. However, they taste nice on the next day. Still I prefer the first method.