Soak the tamarind in 2 tablespoons of warm water1
Dry roast the Toor dal for 3 - 4 mins on a medium to low heat until it begins to give off a nutty aroma and changes colour2. Transfer to the blender jar.
Heat 1.5 tbs of oil in the pan; add the red chilies, onion, salt and sauté until the onion turns translucent3. This should take about 2 mins.
Add the tomatoes, pop a lid on, and allow to simmer on a low flame for 3 – 4 mins until the tomatoes soften4.
Now add this onion – tomato mix and the tamarind to a blender with the dal, and grind to a fine paste5. Taste check and add more salt if needed. The salt must balance out the tang from both the tomatoes and the tamarind.
The chutney is pretty much done at this point; but, if you want to go a step further, heat a tsp of oil in a small pan and add half a tsp of mustard seeds. When they pop, add curry leaves and allow them to crisp up. Turn off the heat and pour this seasoning into the ground chutney. Mix well and serve with idlis or dosas!