Rinse and pressure cook tur dal with water until soft and mushy. Keep aside.
Soak the tamarind in hot water for 10 minutes.
Rinse, peel and cut the drumstick or murungakkai into finger length pieces
After 10 minutes, extract pulp or juice from the tamarind and keep aside.
Heat a heavy bottom pan, add oil, mustard seeds. Once mustard crackles, add drumstick and saute for 1 minute.
Next add tamarind extract, hing, turmeric and let it simmer on medium heat until raw smell of tamarind goes off.
Add sambar powder and cook for 1-2 minutes.
Add the cooked tur dal, water to adjust consistency and mix well. Season with salt, add jaggery, mix and let it reach one boil. Note - Once you mix, taste check salt, spice, heat and add extra, if required.
Switch off the heat, add finely chopped coriander leaves and prepare for tempering.
In a small tempering pan, add ghee, mustard seeds, whole red chillies. Once mustard crackles, add curry leaves. Switch off the heat, add the tempering to the sambar, cover with lid and let the flavors absorb. Serve after 1-2 mins.