I made this Pawzzle bowl on tinkercad, its not overly complicated while still serving the purpose. My dog loves it, I engraved her name on the one I printed for an almost 8.5 inch bowl. I have included STLs for sizes 6.5-8.5. I can also upload a custom name version for you if you like. Leave the name in comments and the size you want and I can have it for you within 24 hours.
The author marked this model as their own original creation.