How to clean belacan?

My mum cooked me sambal petai last week.  Wah, it was so good......

I also learnt a lesson from there - How to clean belacan

Undeniable, there is always lots of sand in belacan.  So, what my mum does is:

1. Slice the required amount of belacan.
2. Put them in a small bowl, then pour some hot water over them. 
3. Soak it until the belacan has melted.  (Note:  It looks rather ..... )
4. Roughly use your finger to press to break down the bigger piece.
5. Pour slowly into the dish during cooking until you see the 'solid'.
6. Throw away the 'solid'.