1-2 fresh thai chilis, sliced or sriracha or red pepper flakes (optional)
Heat the sesame oil in a small saucepan over low heat. Add the ginger and garlic into the oil and stir. Allow to soften and slightly mellow for a few minutes, but don’t allow it to brown.
Turn the heat up to medium, then add in the mirin, soy sauce, vinegar and sugar or agave. Allow the mixture to come to a very small simmer for a minute or two. If using brown sugar, allow it to dissolve completely.
Remove it from the heat and allow it to cool. Add in the thai chilis or sriracha if you want it spicy.
Store in a glass container for up to a week in the refrigerator.
To thicken the sauce, dissolve 1 rounded teaspoon of cornstarch in 1 tablespoon of cold water. Place half of sauce into a small saucepan and bring to a very small simmer. Pour the cornstarch/water mixture into the sauce and stir with a rubber spatula or whisk until thick. Remove from the heat and pour over sauteed or grilled tofu.
Recipe by Olives for Dinner at https://olivesfordinner.com/2013/06/everything-sauce.html