Add low-sodium soy sauce, sesame oil, rice vinegar, brown sugar, and chicken or vegetable broth to a small mixing bowl.

Add cornstarch and whisk everything together until fully dissolved with no lumps.

Stir in 3 garlic cloves, freshly minced, 1 teaspoons fresh ginger, grated, and 0.3 teaspoons red pepper flakes.

Taste the sauce. Add a little more brown sugar for sweetness or a splash more soy sauce for saltiness as needed.

Pour over your stir fry in a hot pan or wok. Toss and cook for 1-2 minutes until the sauce thickens, turns glossy, and coats everything evenly.

Remove from heat. Finish with an extra small drizzle of sesame oil if desired and serve immediately.