What are some quick, healthy lunches I can bring to work?

I am a floater at my job, which means I go to whichever office needs my assistance. Sometimes, I am split between two offices and I have to eat in my car with no use of a microwave. Often, I don’t know I’m being split until I’m actually at work.

Fast food is to expensive to eat every day and I’m not looking to gain 20 lbs anytime soon, so I need some healthy lunches that I can bring to work with minimal prep time. Frozen meals aren’t an option—too much sodium! Plus the grocery bill really adds up when you buy those.

I have kind of a bland taste in food—my burgers/sandwiches are meat and cheese only, I’ve only acquired a taste for a few veggies, I’m not big on salads, etc. I can’t bring leftovers because we normally don’t have enough and our dinners aren’t healthy enough to eat twice a day. I don’t need a big meal, but bringing a banana and nothing else isn’t going to cut it. And soup—sick of it.

I know I’m difficult, but any ideas would be greatly appreciated! Not having anything to bring to lunch is causing me to eat unhealthy things and I already feel like I’ve gained a few pounds.