They seem to sound kinda German to American ears. If Belgians met more Americans I think they'd hear that more often :)
Flemish means "Belgian Dutch" as far as I'm concerned. The northern half (less than half really) speaks this, and the southern half speaks Wallonian which is just Belgian French. Strangely, most people there don't speak both languages. When we travel to Belgium, if we stray further south than Brussel we are down to grunting and pointing.
Because of cartoons, we can say "omelette du fromage" and that's about it.