This copycat recipe for Subway's Sweet Onion Teriyaki Sauce delivers the iconic sweet and tangy flavor with hints of ginger and garlic. Ideal for drizzling over sandwiches, marinating chicken or beef, or as a dipping sauce.
Place the sugar, water, apple cider vinegar, rice vinegar, soy sauce, and tomato paste in a saucepan and whisk to combine.
Add the remaining ingredients except for the sesame oil and bring to a boil over medium heat, whisking constantly. Reduce the heat to low and simmer until thickened, about 4 to 5 minutes.
Once the sauce has thickened, add the sesame oil and remove from the heat. Let cool completely before refrigerating in a sealed jar or bottle.