Add all ingredients (except 2 tablespoons of water and cornstarch) to a small sauce pan and heat on medium.
Bring to a boil for 30-60 seconds and then turn to low and let simmer for 5 minutes.
Add two tablespoons cornstarch to the 2 tablespoons of reserved water and whisk together until there are no more lumps.
Remove sauce from heat, and slowly whisk in the cornstarch and water to thicken the sauce.
Transfer to a mason jar or airtight container and let cool before using or storing in the fridge for up to 1 week.
Notes
If using immediately as a marinade, let cool completely first. Serving Size: 2 Tablespoons Substitutions: Ground Ginger and Garlic: 1 teaspoon of ground ginger and 1/4 teaspoon of garlic powder.Mirin: Sake or Sherry with a pinch of sugar.Brown Sugar: Honey or a brown sugar alternative (to reduce sugar content).