1. In a saucepan, heat 2 Tablespoons of toasted sesame oil to medium-high heat. Add scallion, garlic and red pepper flakes. Lower heat to medium and continue stirring about 3 – 5 minutes or until garlic starts browning.
2. Increase heat to high and stir in Soy Sauce, Vinegar and water and bring to a boil.
3. Add dark brown sugar and stir until sugar is dissolved.
4. Lower heat to low and cook for 10 minutes, stirring often.
5. Makes about 3 cups. (Sauce can be refrigerated in air-tight container for several days).