Although it may be a surprise to some, as a Moe "type", Yandere merchandise can be found if one knows where to look.
This page is for detailing real/official merchandise based on Yandere characters or the "type" itself. Please provide as much information or a picture as possible.
A series of sandwich cookies, each based on the various moe types, such as Yandere, Maids, Tsundere, etc, and has a variety of filling. Each also comes with a postcard with a character fitting the type designed on it.
The Yandere cookie has strawberry-chocolate cream inside.
Unfortunately, these snacks can no longer be found. The original website that sold them is a broken link, given these were made around 2013-2015. It would be great to see a re-release of these snacks.
Original Japanese language article —-> https://www.coade-net.co.jp/blog/19457/
There is also a yandere pie snack.
You can see the review here on a European article —-> https://www.fangirl.eu/2010/04/06/le-truc-inutile-du-jour-la-yandere-pie/
This also comes with a variety of yandere girls to choose from, also comes with a card of the yandere girl of your choice.
Hopefully these snacks make a comeback in the future