Filling, easy lunch ideas!

I'm in college & for lunch I've typically been eating the grilled chicken sandwich from Chickfila for lunch every single day. I'm not necessarily getting tired of it, but I think I'd rather make my own lunches from here on out.

I always accompany the sandwich with about 200 calories worth of peanuts, so thats always my "side". But for the "main course" I guess, I need something quick, easy, & as un-processed as possible that I can prepare with (or without) a microwave only.