Puli Milagai - Indian Pickle with Chilli, Tamarind and Jaggery - Side dish for idli, dosa and yogurt rice

In my childhood days during the season of fresh green chillies (normally around Pongal days) my great grandma used to make Chilli pickle which is most favourite. I can finish the entire Jar in few days. Tangy Tamarind, Sweet Jagger and firey Chillies really fantastic combinations. Now a days you get green chillies almost everyday. I was asking my grandma for recipe.. Finally she found the hand written one. So hear you go with the recipe

Small onion - 20 (chopped )
Green chilles - 15 (Chopped roughly.. I did use bigger variety less spicy one)
Tamarind - Lemon size. 
Turmeric powder - 1/4 teaspoon
Jaggery as needed
Salt as needed
Oil - 2 tablespoon (I have sued gingerly / sesame oil)
Mustard seeds - 1/4 teaspoon
Urad dhal - 1 teaspoon
Asafoetida - A pinch

Soak the tamarind in 1/2 cup of hot water and take thick paste out of it. Keep it aside
Heat the oil. Add Mustard seeds and Asafoetida. Let it crackle. Add Urad dhal fry till slight brown color. Add Onion and fry till transparent
Add Chopped Chilli. Fry for 3-4 mins.Add tamarind paste and Let it boil till you get desired consistency (thick gravy consistency)
Add Turmeric, jaggery and let it boil in low medium flame for another 2-3 mins
Switch it off. Once cool down store it in air tight container. This can last for a week in the fridge
Also goes well with curd rice, idli, dosa etc..