Coat the chicken. Toss the chicken pieces in salt, pepper, and cornstarch until well coated.
Pan-fry until crispy. Heat oil in a skillet over medium-high heat. Fry the coated chicken thighs in batches until golden brown and cooked through with an internal temperature of 165°F. Drain on a paper towel-lined plate.
Make the sauce. In a pan, combine sweet chili sauce, soy sauce, rice vinegar, brown sugar, crushed red pepper flakes, and minced garlic. Simmer for 2-3 minutes until warmed through and slightly thickened.
Toss and coat. Add the cooked crispy chicken to the sauce and toss until every piece is coated and glossy.
Serve and garnish. Top the coated chicken thighs with sesame seeds. Serve hot over steamed rice or noodles.
