ExpandIs the tablet @SchiehallionHandmade mentioned perhaps the Scottish tablet candy, which is basically milk and sugar and sugar and sugar?
Oh, maybe, I'd never heard of that, always fun to learn about different types of sweets ...
https://en.wikipedia.org/wiki/Tablet_(confectionery)
https://www.thespruceeats.com/traditional-home-made-scottish-tablet-435825
Even if it's softer than fudge I would think all that sugar would inhibit mold growth ... already way more than 50% sugar by weight then you cook most of the liquid off 🤔