Bring water to boiling point and remove from the stove.Wash and soak the lemon in hot water for 15 minutes. Remove from water and wipe.
Dry roast methi seeds and grind to coarse powder. Mix all the masala red chilli powder, salt and methi seeds in a big container.
Cut the lemon into four pieces. Since it has lot of juice cut lemons carefully, else the juice will enter your eyes. Add the lemon wedges and juice into the masala.
Heat sesame oil for 5 minutes. Add in mustard. Let it splutter and add hing (asafoetida) powder. Remove from stove and wait for oil to cool.
Now add the oil at room temperature to the lemon. Place a lid and leave it to soften for 24 -48 hours. You can mix it once or twice .
After 2 days you can transfer the pickle to a porcelain jar or air tight bottle. You can place this in the fridge.
Lemon takes 4-5 days to soften . Then Lemon Pickle is ready to serve.