Cut the chicken breasts into bite-sized pieces.
Coat the chicken with corn starch.
Heat vegetable oil in a skillet over medium-high heat.
Add chicken to the skillet and cook until golden brown.
Mix sweet chili sauce, soy sauce, rice vinegar, Sriracha, garlic, and sesame oil in a bowl.
Pour the sauce over the cooked chicken and stir.
Simmer until the sauce thickens slightly.
Garnish with sesame seeds before serving.
Serve hot over rice or with vegetables.