Dissolve cornstarch with 1/4 cup of the water and set aside. In a saucepan over medium heat whisk together the remaining water, sugar, rice wine, sriracha, garlic powder, and red pepper flakes.
Bring the mixture to a boil and lower the heat. Add dissolved cornstarch to thicken. Simmer for another 3-4 minutes then remove it from the fire. Allow it to cool before storing it in a tightly sealed jar. Refrigerate for 7-10 days.