Anko is a sweet red paste made from adzuki beans, which is used as an ingredient in many Japanese sweets. One of the most popular of these is anpan, a small bun with anko baked inside as a filling. The confection was invented by Kimura Yasubei, a former samurai-turned-baker, who presented this new dish to the Meiji Emperor on April 4, 1875. The Emperor was so impressed with the anpan that he asked Kimura to supply them to the Imperial Household on a daily basis. Today, Kimura's bakery, Kimura Sohonten, still observes April 4 as the anniversary of their most famous dish.