This sauce is similar to the Yoshida sauce that can be found at costco and other stores. Note that this is not an exact copy but a very similar taste that can be made with ingredients that can be found in your kitchen and not a laboratory.
Combine soy sauce, 1/2 cup brown sugar, 1/2 cup white sugar, green onions, ginger and garlic in a 2 quart saucepan. Bring the mixture to a slight boil. Reduce the heat to low and simmer for 15 minutes.
Pour the remaining white and brown sugar and the honey into the saucepan. Bring to a boil. The mixture will rise and foam, when it does this and doubles in size remove the pan from heat and cool.