In a medium bowl, whisk together the low-sodium soy sauce, rice vinegar, grated ginger, minced garlic, brown sugar, sesame oil, red pepper flakes, and cornstarch until smooth.

Place the chicken thighs in a large bowl or zip-top bag. Pour the marinade over the chicken, ensuring thorough coating. Refrigerate for at least 30 minutes.

In a separate bowl, combine the sauce ingredients and whisk until well blended. Set aside.

Mix equal parts cornstarch and water in a small bowl to create a slurry; set aside.

Heat oil in a large skillet over medium-high heat. Add the marinated chicken, cooking for 3-4 minutes per side until golden brown.

Remove the chicken and pour the sauce mixture into the skillet, scraping up any browned bits. Simmer for 2-3 minutes.

Gradually add the cornstarch slurry, whisking continuously until the sauce thickens.

Adjust seasoning to taste and return the chicken to the skillet to coat in the sauce, heating through.

Stir in a splash of sesame oil and garnish with green onions and sesame seeds before serving.

Serve over rice for a complete meal.