What it basically is, is chocolate sprinkles you eat with bread and butter. The little boxes above the bread board at the hotel was the first thing I went for, and as odd as it seemed to my outsider eyes, it really is a wonderful snack/breakfast treat!
The Sprinkles (or curls if you feel fancy) are much different the the waxy ones we see here in the States on top of ice cream. They are extra chocolaty and genuinely tasty!
It is fairly easy to pick up some of the hagelslag here in the States from either World Market or Amazon. Once you have them all you need a a nice slice of good bread (preferably brown) a bit of butter spread across it to hold the sprinkles in place, then pour on as many as you fancy and enjoy!
We got a nice selection from a grocery store by the hotel you wouldn't believe the selection available over there! I hope you'll give it a shot as well, you'll feel terribly continental and like a happy kid all at the same time!