Step 1: Combine water, rice vinegar, honey, granulated sugar (if using), minced chilies, minced garlic, grated ginger, soy sauce, sesame oil (if using), and salt in a medium saucepan.
Step 2: Bring the mixture to a simmer over medium heat, stirring occasionally. Let it gently simmer for 5-7 minutes, allowing the flavors to meld and the chilies and garlic to soften.
Step 3: Taste the sauce and adjust sweetness or heat as desired. If you want more heat, add a pinch of chili flakes. For more sweetness, add a little extra honey or sugar.
Step 4: Whisk the cornstarch slurry until smooth. Slowly pour the slurry into the simmering sauce, whisking constantly to prevent lumps.
Step 5: Continue to simmer and whisk for another 2-3 minutes, or until the sauce thickens to your desired consistency. It should coat the back of a spoon.
Step 6: Remove the saucepan from the heat and allow the sauce to cool completely. As it cools, it will thicken further. Once cooled, transfer the sauce to an airtight container. I love using Basics Glass Food Storage containers for this, as they don’t stain and keep flavors fresh.
Step 7: Store in the refrigerator for up to 2-3 weeks. Shake well before each use.