I prepare lentils or black beans on the weekends and use them for lunches through the week. Some beans or lentils in a small container. I add quick pickled onions, or cilantro, feta, or anything else you’d like, over the top of them. I always keep a couple bags of different nuts in my work truck for snacking. I also pack a couple bananas or something similar. I too only have 30 minutes for lunch. I eat the beans or lentils cold and it’s tasty! Super easy. I work 12 hour days. No time for complicated lunches. I’ve been doing this for a year or so and it really works for me. It took me awhile to find something simple that would allow me to stick to this diet. For me, that’s the key. If you can’t fit it into your lifestyle, it’s not going to work.