Firstly, take 2 Kashmiri chilies, cut them from the top, remove maximum seeds from them and soak it in water for 10 minutes.
Now chop onion and tomato into small chunks and keep them ready.
Heat mustard oil in a pan and add peanuts and fry them till they turn brown for 2 minutes. Remove them on a plate and keep them aside.
Heat oil in the same pan and add onion and tomato chunks, garlic, soaked red Kashmiri chilies, and saute for 2-3 minutes.
Now add Tamarind paste, jaggery piece, salt, mix everything well, and cook for another 1 minute.
Add roasted peanuts that we had fried earlier and mix everything well and cook for 1 minute. Switch off the flame and let it cool for 5 minutes.
Transfer all the ingredients into the grinder and make it into a smooth paste, add little water for a smooth paste. Finally, remove the peanut chutney into a bowl.
For Tempering / Tadka
Heat oil in a small pan, once the oil is hot add urad dal, once it turns brown, add mustard seeds, once they crackle add curry leaves.
finally, switch off the flame and pour this Tadka/ tempering on peanut chutney and serve.