Place the first six ingredients into a blnder and process until smooth. Transfer to a pan and bring to boil over moderate heat. Reduce heat when it boils and simmer until thick enough to coat a spoon about 5 minutes. If too thick add a bit of water. Set aside to cool.
Garnish with the paste and peanutes. Also you can use garlic, chilies and ginger.
Keeps 2 weeks.
Note if you can't find the soybeans omit it and use 1/3 cup hoisin sauce letting out the sugar.