Heat up the sugar with the mirin. The sugar will melt and the alcohol will heat up and evaporate. Simmer over a low to medium heat setting for 2-3 minutes but don't boil.
3 Tablespoon Mirin, 2 Teaspoon Sugar
Allow the mirin sugar mixture to cool down a bit.
Pour mirin sugar blend into a mixing bowl. Add soy sauce, rice vinegar and citrus fruit juice to it.
5 Tablespoons Soy Sauce
Use with your food instantly or store in a glass jar for later use. See post for serving ideas.
Use plain regular Kikkoman soy sauce.
The rice vinegar should be mild. If it's a strongly flavored very acidic rice vinegar, reduce it by a 1 tablespoon from the basic measurement.
Traditionally, yuzu citrus fruit juice is added to flavor a ponzu sauce. You can also use lime juice if you don't get yuzu where you live. Yuzu is more flavorful so you will only have to add 12 drops to the basic recipe. When using lime juice you will need to add more, for the basic recipe about 1 teaspoon