I have visited Brussels Amterdam and Bruges.
If you are in Brussels I'd say go to Bruges rather than Hamsterjam. Hamsterjam is good but deserves several full days/nights. Bruges is very scenic. Also closer/cheaper to get to from Brussels giving more time in the place.
BTW Good Belgian Food can be absolutely brilliant, better than French at the same price - there is a lot more to it than Moules.