- 1 cup (packed) light brown sugar
- 1 cup mirin
- 1 cup reduced-sodium soy sauce
- Bring all ingredients to a boil in a small saucepan over medium heat, stirring to dissolve sugar. Reduce heat and gently simmer, stirring occasionally, until slightly thickened, 40–50 minutes; let cool.
- DO AHEAD: Teriyaki sauce can be made 1 month ahead. Store airtight and chill.