Fries (Frites) are one of the most common foods found. Lots of store owners call them Freedom Frites when they see that theres an American ordering. And they are much better than any fries in the US. No doubts about it. 

Cantillon Brewery

The first King of Belgium (Leopolod) saw this house while traveling, so of course he had them take it apart and shipped it back to Brussels to have as a lawn ornament.

Mussels and frites. Pretty big deal in Belgium.