Bring the soy sauce to a boil, add the sugar and slices of ginger and stir. As soon as it boils, remove from the heat and add the balsamic vinegar and truffle oil. Sesame oil can be substituted for the truffle oil if you prefer but the sauce will loose some of the unique flavor.
This striking pot de creme cup was manufactured in Paris, France by the CH. Pillivuyt & Cie company.