Serve over your stir-fry once it's complete.
3.5 oz Soy Sauce (MUST Be Kikkomans)
2.0 oz vegetable oil
2.0 oz vinegar
1.5 oz water (or sake)
3.0 oz onion, chopped
1.0 oz ground fresh ginger
Add all ingredients to blender or food processor. Mix until smooth. Refrigerate for an hour before using.