Lunch Ideas for my Fiance- Portable and Grain Free

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My fiance has recently found out that he is intolerant to many grains- wheat being the one that effects him the worst. He also works outside and is on the move a lot and has a large lunch box with a cold pack. Do you guys have any ideas for healthy, filling lunches that we can make for him?

Must be: Grain free, semi-portable, somewhat low in dairy (we aren't sure if he is allergic to that yet), filling and healthy.

Thanks MFP!!