Preheat your oven to 400°F (200°C). Lightly grease a 9x13 inch baking dish.

In a small bowl, whisk together the cornstarch and water until smooth to make a slurry.

In a larger bowl, combine the sweet chili sauce, soy sauce, rice vinegar, minced garlic, and minced ginger. Whisk well.

Pour the cornstarch slurry into the sauce and whisk again to combine.

Place the chicken thighs in the baking dish and pour the sauce over them, ensuring each piece is well coated.

Bake in the preheated oven for 30-35 minutes, or until the chicken is cooked through and reaches an internal temperature of 165°F (74°C).

Remove from the oven and garnish with sesame seeds and chopped green onions, if desired.