Wash the lemons and peel off any stickers that are on the lemon skin.
In a large pot, heat water (enough to completely submerge the lemons). Let the water come to a rolling boil. Now gently drop the lemons into the boiling water and turn off the flame. Cover the pot with a tight lid and keep it aside.
Let the water cool down to room temperature before we proceed to the next step. I added the lemons in the boiling water at night and then let it sit overnight. I proceeded to make the pickle the next day morning.
Once the water had cooled down entirely, remove the lemons from the water. The lemon would be very soft and squishy and this stage.
Chop the lemons into desired shape. Lot of juice will flow out when you cut the lemons. Save all the juice as we will add it to the pickle. I used a plate to chop the lemons and kept draining the juice and the chopped lemons into a large non-reactive bowl.
To the chopped lemon, add the salt, chili powder, asafetida and roasted fenugreek powder.
Heat the oil in a pan and add the mustard seeds.
Once the seeds crackle, add it to the bowl with the rest of the ingredients.
Mix well and let it sit overnight in the bowl (covered).
Transfer the pickle to a sterilized jar and keep it airtight. The pickle should keep well outside, since it has quite a bit of oil in it. I am planning on storing it in the refrigerator after couple of weeks. This will give time for the lemons to keep getting softer
The pickle can be consumed the next day itself. I found the lemons to be quite soft and delicious to eat.