Peel and chop the ginger finely and soak in a little hot water. Chop the green chilies. Drain ginger. Put ginger, chilies, curry leaves, into a pan. Add a little water and salt. Cook over a slow fire till dry. Roast red chilies fenugreek seeds and powder fine. Soak tamarind in a little hot water. Heat oil in a pan. Add mustard seeds; when they crackle add cooked ginger mixture. Saut till the mixture turns brown. Remove from fire and add red chili and fenugreek powder. Add tamarind water. Return to fire. Add salt and Jaggery or Sugar and bring to boil.