Mix both the dals and wash them thoroughly. But twice the amount of water and give it a boil. Add turmeric and boil till dal is completely mashy.
In a separate pan heat oil and add heeng mixed with 2 tbl spn of water. Add mustard seeds and curry leaves. Now add sliced onion and garlic pods. Sauteon low heat and then add the madras curry powder. Sauteon low heat and then add the mashed dal and cook for 5 mi-nutes.
Add the tamarind paste and garnish with fresh coriander leaves.