Wash bitter gourds and cut into two length wise. Remove seeds in the center and discard them. Cut the deseeded bitter gourd into cubes. Keep aside.
In a saucepan, roast coriander seeds, mustard seeds and methi seeds on medium low heat until the mustard seeds start to splutter and the whole mixture turns light brown; about 2 to 3 minutes.
dd the dry red chillies, broken into 2 or 3 pieces and fry again for 1 minute.
Just before removing from heat, stir in asafetida powder, give it a good mix and keep aside to cool.
The heat of mixture is enough to roast the hing.
Once the mixture is cool, blend it along with a small lemon sized piece of tamarind to a powder.
In a large deep saucepan, add plenty of water to the chopped bittergourds to up to 1 inch above the vegetable.
Bring to a boil on high heat and once it comes to a boil, lower heat, cover and cook on medium low heat until it is cooked, and soft and almost done.
Once it is cooked, add the spice powder, jaggery and salt, mix well and bring to a boil again.
Once it comes to a boil, lower heat and simmer on medium low until the pickle becomes thick; about 15 to 20 minutes.
Adjust the jaggery and salt to get a balanced sweet and salty flavor with a slight tang of the tamarind.
In a small saucepan, heat coconut oil and add mustard seeds. Once the seeds start to pop and crackle, add the curry leaves and saute for a few seconds.
Pour this over the pickle and mix well.
Enjoy with hot rice and dal, with dosas (Indian rice-lentil crepes), idlis (lentil-rice steamed cakes) or any Indian flat bread like puris, chapattis, parathas etc.
Store leftovers in the refrigerator for up to a month.