Soak the tamarind in one litre of lukewarm water for 15 minutes. Then grind it into a paste. Strain into another bowl.
Place on low heat and add turmeric and red chilli powder.
Add the chopped ginger, chillies and curry leaves; continue to cook on low heat till bubbles appear at the edges.
Add the jaggery and season with salt.
At this stage, it is important to taste and adjust the flavours; it should be a perfect balance of tanginess, heat, aromatic ginger and sweet. If you feel any of the flavours are out of proportion, adjust accordingly.
Add the roasted fenugreek powder and mix well.
Lightly roast the rice flour and add to above, to thicken the chutney.
Once the chutney has thickened, remove from heat.
Add a tempering with oil, mustard seeds, fenugreek, dry red chilli and curry leaves.
Cool and store in air tight bottles or containers. This chutney can be stored for upto a month when refrigerated; i.e. if it lasts so long!