Apparently not so easy. My usual go-to vegetarian soups all seem to contain milk or butter. I also made the annoying discovery upon a closer inspection of the ingredient list that Campbell's Thai Tomato Coconut isn't even actually vegetarian because it has anchovies. Oops. I ended up settling on Amy's split pea (helpfully marked vegan by the ingredient list).
The verdict: eh. I needed to add several of those little to-go packets of pepper that accumulate in the office drawer to give it some extra flavor, and it still wasn't exactly exciting. But it was filling enough and got me through lunch, which is enough I suppose. I'll definitely need to make more of an effort to seek out quick lunches that I can turn to when I don't have time for any other preparation. Any suggestions?