Does anyone have a recipe that uses Garcinia Slices?

Thank you for your response. I'll search around for recipes using dried mangosteen, I really didn't find much when I searched for Garcinia.

I suggest you use a search engine (one that covers the Internet like Bing, Google or DuckDuckGo, not a site-specific one like Food52's) and search for "dried mangosteen" which is the more commonly used name for Garcinia.

You will find some recipes that use it as an ingredient.

You should consider asking the person who gave you the slices how they use them.

Best of luck.