I've been seeing this come up in Ask a Manager discussions of work meals. I like the theory of trying to make sure that everyone can eat _something_, rather than everyone can eat everything, and just being clear about what's what. But on a small personal scale, that might lead to more leftovers than desired.

Pinewoods Dance Camp has one of the most impressive dietary-restrictions-friendly kitchens I've ever seen. I'm friends with their head chef, and I've enjoyed watching how thorough they are about collecting information each session. They make sure food is always clearly marked, alternatives are provided, and everyone is accounted for! The camp is celebrating its 100th year in a couple years, and various people are working on a cookbook --I get a chance to test out the vegan chocolate cake that's my favourite camp dessert (as someone who's plenty omnivorous!)

~Sor