Add the soy sauce, orange juice, water, rice vinegar, sugar, cornstarch and red pepper flakes in a small bowl. Whisk well to combine and set aside.
In a small saucepan over medium heat, sauté the garlic and ginger in oil until fragrant.
Add the sauce to the pan and bring to a gentle simmer.
Continue to simmer, whisking frequently, until the sauce thickens to your desired consistency, about 3-4 minutes, or until it coats the back of a spoon.
Remove from heat and use immediately or let cool and store in the fridge for up to 5 days.