Heat vegetable oil in a pan.Add peanuts and fry until slightly browned.Remove them in a plate.Add red chilli, ginger, garlic and onion in the pan and fry for 3-4 minutes.Add them in the plate with peanuts.Let the peanuts and other ingredients cool.Transfer them in a grinder along with tamarind and salt.Add some water and grind to make a smooth chutney.For tempering, heat oil in a pan.Once the oil is hot, add mustard seeds, cumin seeds and hing and let them crackle for a few seconds.Add urad dal and fry until browned.Add curry leaves.Pour the tempering over the chutney and mix well.Serve the chutney with dosa, idli or rice dal.