Roast sesame seeds in a pan without fat until golden brown. While still hot, crush finely in a mortar. Mix evenly with sugar, miso, vinegar, sake, soy sauce and mustard
Tip: Japanese mustard: Mix 5 teaspoons of mustard powder with hot water to a soft paste. Let it swell for 15 minutes. It is used for the sesame sauce and as a side dish with meat