As a vegetarian I have a hard time finding edible food in our work cafeteria. So I started bringing my own noms instead.
For the worshippers of ease there are gazillions of tasty soups and stews, for the lovers of cuteness and healthy food there is the Japanese tradition of bento. All of them require similarly dimensioned boxing, so a single carrying device should be sufficient.
I found this very good bento bag tutorial – I will just use less colours for mine: