Potato Gratin consists of thinly sliced potatoes baked in a rich and creamy sauce. While simple, its browned surface is especially appetizing, making it a universally appealing dish. Known as scalloped potatoes in the US, many countries have their own version of this dish. Japan has embraced it as well, and it’s now a western-style Japanese dish commonly found in restaurants and home kitchens. This combination of potatoes and béchamel sauce is popular among both the young and the old.