Heat 2 tsp of oil in a pan and saute this zuchhini till it is well cooked. Let it cool completely
Heat the rest of the oil in another pan. Now add the black gram dal, chilly, fenugrekk seeds and asafoetida and saute well. Cook on a low flame till the dal starts to brown. Switch off the fire and let it cool completely
Now transfer the fried dal, zucchini, tamarind and salt to the mixer jar and grind it into a smooth paste adding the required amount of water..
Heat 1tsp oil in a pan and add the mustard seeds. When it starts to splutter , switch off the fire and add it to the prepared thogayal