Preheat oven to 375°F (190°C).
Rub chicken thighs with olive oil, then season with salt and pepper.
Heat an ovenproof skillet over medium heat and place chicken thighs skin-side down.
Sear for 3–5 minutes without moving until lightly browned.
Remove chicken and discard excess drippings from the pan.
In a bowl, mix brown sugar, soy sauce, vinegar, ginger, and garlic.
Return chicken to the pan, skin-side up.
Pour sauce over the chicken evenly.
Roast for about 25 minutes, basting occasionally, until fully cooked and juices run clear.
Spoon the glaze over the chicken before serving for maximum flavor.