In terms of Viet food, pho. It's literally the only Viet dish a lot of westerners know. So much so that on a video of another Viet noodle dish in broth, some people were criticizing the way it's cooked and how it looks flavorless, and then a bunch of well-meaning white knights swoop in and say "ummm that's pho, that's how they cook it!" but it's actually an entirely different dish