It's a beautiful thing, preparing the same lunch every day.
It's strangely freeing, something you wouldn't expect from something so regimented and unchanging, and over time my enjoyment of lunch seems to increase in spite of all the things staying the same. While it started out of desperation, I've ended up with a balanced $4 meal I can cook (and clean up) in 10 minutes with ingredients from the corner store that I thoroughly enjoy, leaving me time and mental energy for the things that really matter.
It started a few years back: being someone that just wanted my lunch to get over with, and for something healthy and consistent, I got really big into Soylent. I could carry around a bottle and a pouch of powder, and so long as I could find water, I had all the nutrients I needed that day - awesome! Soylent stayed a significant part of my diet all the way until I moved to Japan. Unfortunately, they don't ship there, which left me with no lunch strategy. I subsisted on things I could buy at the local conbini, slowly learning that I couldn't eat more and more things, thanks to the Japanese insistence on putting animal power in everything. Seriously, like 80% of potato chips here are seasoned with animal products.
"But Stuart," as I've heard before, "food is an art! Eating the same thing every day is an affront to all the options out there!" Let's get this one out of the way. Sure, you can spend your time seeking out truly new and novel cuisines. For me, maintaining a healthy diet is too difficult with that much variance, and I would rather spend that time elsewhere. Success takes a lot of consistent effort, and I would rather spend my time on my work than in finding new cuisines to explore.
Back to the story - one day, my genius of a wife made us a simple dinner (one of the easy meals she figured out while I was gone) made up of yakisoba noodles, chopped vegetables, and fried tofu. It was tasty, most of the work was done already (tofu already fried in triangles, vegetables sold chopped in a bag), and best of all, there were few dishes involved (if you remember my adoration of doing the dishes). I was stricken - had I found my new Soylent?
It started slowly - I would cook the meal once or twice a week, slowly improving my process, adding peanuts to increase protein content (and improve the flavor!), and figuring out how to use even fewer dishes. Before I knew it, I was eating it almost every day. The process was liberating, the only mental energy I had to spend before lunch was checking if I needed to get more peanuts or noodles before walking to the store. I would hit a breaking point in work, head to the store and pick up the materials, cook things, washing the dishes in between stirring the fry, and then boom, big bowl of veggies, tofu, peanuts, and noodles.
The slow improvement in cooking was not surprising: finding cues for when the tofu had cooked enough, or how long the veggies and peanuts should be in until the frying was done, etc - it was obvious that I was always looking for ways to improve the cooking. The thing I didn't realize until much later was that I was also practicing appreciating the dish. I got better at eating it - at being able to pick up the right components of a good bite (tofu chunk, a little bit of noodles, a crunchy piece of cabbage, and a few peanuts - the peanuts were the hardest part).
The whole process has become satisfying and useful - I get a healthy and tasty lunch for cheap, I clean some dishes, I can spend my time thinking about other things: win, win, win!