I keep a big carton of old-fashioned oats, craisins, cinnamon, sliced almonds, coffee, peanut butter in my desk along with a deep bowl, paperplates, flatwear, glass mug. When I'm regularly commuting I bring a week's worth of bread on Monday, power bars and some fresh fruit. Then each ride day I'll bring a snap-lock box with yogurt, anything else I want, a waterbottle with cold latte (nuke at work). My desk job allows me to have breakfast while booting up the computer and checking my email. I have a coffeemaker and microwave in my cubicle. Sometimes I'll bring in cold grilled chicken or salmon and buy a simple salad at the cafeteria.
My commuting ... sigh ... insomnia, workhours and weather have not played into my favor. Generally I have to allocate 2 hours for the commute+cleanup each way. It only works if I can log some short workdays when I ride, can wake up early, and if weather is reasonable.