Put the miso, sugar,sake into a medium sized saucepan and bring to a boil, stirring constantly. Reduce heat and, and simmer for 30 minutes, stirring occaisionally. Remove pan from heat and wuickly beat in 2 egg yolks, 1 at a time. Immediately dip the bottom of the pan in ice water to cool rapidly. The dressing may be used in Nuta-ae, Nasu Karashi Sumiso-ae, or Kinome-ae.