Do you mean beschuit?
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The Germans call it zwieback, from 2 times baked. I believe in the production process they are twice as thick to start when baked the first time, then sliced horizontally and baked until crispy and airy and yummy!
They are indeed wonderful with butter and cheese, or with hagelslag! (look it up and make your own, much better version by grating chocolate. Hagelslag is a perfectly acceptable topping on a breakfast or lunch sandwich for grown ups in the Netherlands

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I'm not sure about the banana on my cheese, but now I've found I like marmite on my chocolate I won't say I won't like it until I tried. Which I probably won't
I still eat beschuit once in a while, depending on the brand they can be as low in carb a piece as 6.5 grams, but they're very fast acting for me.