Harusame are translucent, thin noodles, originally made in China from the starch of ryokuto (green mung beans). The Japanese adapted the main ingredient to create noodles from potato and sweet potato starch. This method became widespread during the post-war period and remains popular in Japan today. Harusame noodles are available in dried form and need to be soaked in water before using. They have a naturally tender texture that lends itself to a variety of dishes including soups and salads.