Soak tamarind in water for 30 minutes, squeeze out the pulp after tamarind softens. Pulp is ready to use.
Soak dry red kashmiri chillies in water for 30-40 minutes. Heat 1 tsp oil in a pan and roast chana dal till it turns golden. Add curry leaves, soaked red chillies and pinch of hing. Add choped tomatoes and salt to taste. Cover and cook till tomatoes softens. Cool it to room temperature and grind it to a smooth puree nd add tamarind pulp (to your taste).
For tempering : Heat 1 tsp oil and add rai(mustard seeds), let it crackle and add 1 dry red chilli. Pour the tempering on chutney and it is ready to serve.
Tomato chutney is a south indian accompainement usually served with idlis, dosas, medu wadas or steam rice.