I normally just bring something complicated that takes microwaving. Stews, braised meats, anything that will go in one single tupperware container and allow for a decent nuke result. Alternatively if you're finding it difficult to get some good grub you could always cut down to two meals a day and just do breakfast/dinner. I did that for a while but I'm not much of a breakfast person so I swapped back to only lunch/dinner but it might work for you.
"You can demonstrate the purpose and limits of human digestion with a simple experiment: eat a steak with some whole corn kernels, and see what comes out the other end. It won’t be the steak."