Using a measuring cup, measure the 1/2 cup peanut butter and place into a mixing bowl. Add 1/3 cup (half of the total water) into the bowl and carefully whisk a little bit. (It will look curdled).
Add two tablespoons hoisin sauce (I used Tan Tan Foods hoisin sauce) and fish sauce, if using. Whisk together until well blended.
Add the remaining 1/3 cup of water and whisk together. It will be nice and smooth and creamy. If not, add a little bit more water (this will depend on how creamy or thick your peanut butter is to begin with).
Add minced garlic and the teaspoon of sugar and whisk again.
Serve immediately with spring rolls or store in a fridge in a sealed container for about a week. (Makes about 1 cup and 2+ Tablespoons of peanut sauce.)
