I think. The most popular Japanese food is TKG. (Tmago Kake Gohan) The recipe is easy! Only you need is to be brave maybe. Prepare a fresh egg, a little soya sauce and rice. At first, stir fresh egg with soya sauce and just pour on the rice. Our guest from USA was surprised at hearing this easiest and the most poplar Japanese food. He asked me, 'Don't you cook? Do you eat raw egg?' I told him, 'We just eat. We don't use fire. It is very popular food in Japan and everybody knows it.' It is very simple but very delicious. Why don't you try it at home? Sorry we don't serve it at the restaurant.