The actual food items I suggested were a bit of a joke, but the food science and baking store suggestion you offered are excellent.
It looks like the closest fit for a baking supply store is a Williams Sonoma, otherwise I’ve got an hour+ drive of me. But it’s on the list for next time we travel to more populous cities!
Edit: A local (hour drive away) baking shop has a pretty comprehensive website. I’ve learned that Vanilla powder exists and I might wind up buying edible metallic powders to put on things that shouldn’t be those colors.
We’re doing a ‘super soft’ birthday for one of our dogs this year. My whole paradigm for decoration and (human) foods has shifted.