Peel the lemons (removing the yellow rind) and then cut into small bite size pieces. Discard the seeds. Place in a strainer that is placed over a dish. Collect the juices and reserve.
Heat a small pan or cooking pot and add the oil. When hot add the mustard seeds and the fenugreek seeds. When they splutter, add the lemon pieces and saute for 2 mins.
Add all the spices and salt and sautee for 1 more minute. Turn heat off and add the vinegar and the sesame oil and stir to mix. Pickle is ready to be served immediately!
Store pickle in an air-tight container at room temperature for a week and in refrigerator for about 2 weeks.
Notes
Although I used regular lemons, you can use same recipe to make vadukka puli (Meyer lemons)achar
Recipe by Cook2Nourish at https://cook2nourish.com/2017/09/instant-lemon-picklerelish-vadukkapuli-achar.html