So I suppose it's not really a surprise I've found food so fun to read and write about, because I understand how intimately food ties into identity and culture. And honestly, it's just a plain fun part of world building.
What your characters eat will largely depend on their environment, culture, and economic status, so their food can say a lot about them. In Beyond the Red for example, Eros's first exposure to the luxurious, imported food Kora regularly eats is a huge reflection of the two very different lives they led before their paths crossed. In a WIP I'm working on with Cuban and Mexican characters, where their cuisine intersects and diverges is a marker of the way cultures in proximity interact and influence each other.
The nice thing about writing food is you can usually slip it in naturally without much effort—after all, characters have to eat. Meal times provide a great opportunity to build the character's world and culture and subtly reveal details about them. What's their favorite food? What do they hate to eat? Do they like to savor their food, or do they just eat whatever because they have to? Food can be a point where your characters come together or diverge depending on what you want to accomplish with it.
Finally, food provides an easy place to put details that can give the world a sense of verisimilitude. After all, every place on earth has some kind of local cuisine—and your world should be no different.
How do you use food in your writing?
What do your characters eat? Author @Ava_Jae discusses this fun aspect of world building and how it can be used. (Click to tweet)