What's something filling that can be unrefrigerated for several hours?

I'm going to be traveling several hours to attend a family party for the holidays and sleep there overnight. I don't want them to have to worry about vegan cooking, so I want to bring something that I could eat for both dinner and breakfast, and potentially share with anyone who'd like to try it. Ideally it would be filling enough so that I won't be lightheaded if it's the only thing I could eat.

The only thing I can think of so far is maybe a bread made from lentils? Something like this:

https://elavegan.com/lentil-protein-bread/

Do you have any other ideas? Or even something else I could bring with the bread to make it look more like a meal?