Japanese Hamburger Steak (aka Hamburg or Hambagu) is one of the most popular western style foods in Japan. People of all ages just love the juicy steak made of ground beef (and/or pork) mixed with onion, egg, and bread (or panko.) It’s like a gigantic meatball or individually served meatloaf. While the most typical sauce is somewhat like gravy mixed with tomato ketchup, there are also many popular variations such as teriyaki-glazed.