Soak tamarind in very little warm water. This is done so that the tamrind grinds easily.
Grind all the ingredients for the ground masala into a smooth paste without adding water
Meanwhile, Cut the cucumber into small pieces. Take out the seeds if there are any in them.
Mix the ground paste with the cut cucumber. Mix well. Test for the salt and add if necessary
Heat oil in a kadai, add mustard seeds. Once it splutters add the curry leaves and asafoetida and pour this on the prepared gojju.Serve with hot rice!!
Notes
You can reduce the amount of chillies and jaggery to suit your taste