Really, this should be on Rhodium's site. Sure, it's super basic chemistry... in fact, even takes a bit longer than using NaOH... but it's using a product, baking soda, that is food grade instead of using a potentially unknown and unsafe grade of NaOH. (ACS is fine, but who gets their chemicals straight from Fischer?) Plus you don't need half the care to handle baking soda compared to caustic soda.
The whole post is here: Post 250972 (https://www.thevespiary.org/talk/index.php?topic=9046.msg25097200#msg25097200)
(Chromic: "GHB from GBL & baking soda", Methods Discourse)
The basics of it is:
Bring 400mL water and 97.6g baking soda to a medium boil. Reduce heat to simmer, add 100g GBL (88.6ml) and cover. Simmer for about 20-30 minutes. The pH will end neutral--and small amounts of Na2CO3 are not dangerous to consume.
If you rewrite it into a form suitable for inclusion in https://www.thevespiary.org/rhodium/Rhodium/chemistry/ghb.html (https://www.thevespiary.org/rhodium/Rhodium/chemistry/ghb.html)
(you know what writing style and length is appropriate), I'll put it there right away.