Salamat pagi,
There is a large Indonesian community here, and many people of Indonesian or mixed (called 'Indo') descent for historical reasons. There are also many Bahasa Indonesia words in Dutch language (and vice versa).
Basically, Indonesian food is to Holland, what Mexican would be to California or Texas, or what Indian food would be to someone in England. It's something you DO.
Naturally,sambal is very popular here also. There are at least 30 different kinds.
A lot of people make their own sambals.