well that's not exclusive to France but it's happening right now and most of the board doesn't know about it
during epiphany (
https://en.wikipedia.org/wiki/Epiphany_(holiday ) we have a family dinner where the dessert is a King's Cake, which can be different things but most of the time it looks like pic related, and there's a small porcelain figurine hidden in it, and the person who finds it in their slice wears a plastic crown and depending on what the tradition is where you live can buy everyone else a drink or whatever
the traditionreally changes with your geographical location since it's from the greek/roman era, but where I come from the cake is some kind of big round donut-shaped brioche with sugar on top of it, and sometimes candied fruits, and the youngest person at the table has to hide under it and the person who slices the cake asks them " who's this one for " and they'll answer with a name
