Cook ash gourd bondu along with cumin seeds, red chilly and little water.
Add cooked bondu mixture, grated coconut and salt in a blender and grind it to fine paste adding water as needed.
Now put this in a bowl, add curds and mix it well. The consistency of tambuli should be thinner than chutney. So adjust the consistency by adding water.
Now in a small pan heat oil, add mustard seeds, urad dal, red chilly and curry leaves. When mustard seeds splutter add it to tambuli.
Now ash gourd bondu tambuli is ready to be served with hot rice.