I only realized that dutch people are handful communicators when moving abroad. Apparently I do it unconsciously all the time.
For example we gesture when something tastes good and I don't even say "tastes good" out loud i just wave my hand next to my cheek. But quickly learnt that people think you're crazy in the head instead of complimenting the chef.
I also learned in an awkward way that waving my hand next to my cheek isn't an international sign for lekker. I moved to Canada about 20 years ago, and still sometimes do it, but apparently here it means you're signaling that someone is a little bit crazy.
Are you sure you are not licking your fingers?
https://www.learndutch.org/beginners/expats-about-nasty-expe...
https://www.reddit.com/r/Netherlands/comments/14kn2ei/i_thin...
https://dutchreview.com/culture/gross-things-dutch-people-do...
Now I wonder if mixed Italian-Dutch children have two different forms of communication by gestures. Would be interesting, especially since neither are true sign languages.
Eating only half a pepernoot and putting it back in the bowl is crazy behavior.
In this case the gesture is to not speak with a mouth full of food, which is understandable.
Also, she made the gesture twice without saying "mmmmm" while making it. Imo, that sound is part of the gesture.
Italians have a gesture for this as well, and it speaks for itself: nobody says "mmmm" while doing it.
Needs the sound! Otherwise, even other Dutch people will look crazy at you. :)