Combine soy sauce, brown sugar, mirin, pineapple juice, rice vinegar, grated ginger, minced garlic, and sesame oil in a bowl. Whisk until the sugar mostly dissolves.

Taste the marinade; if it’s too sharp, add a teaspoon of honey.

Place chicken in a shallow dish or resealable bag and pour half the marinade over it. Reserve the other half in the fridge for glazing later.

Let the chicken sit for at least 20 minutes (up to 2 hours) to marinate.

Heat a large skillet or grill pan over medium-high heat. Add a touch of oil and lay chicken pieces down—don’t crowd them.

Cook thighs about 5–6 minutes per side (breasts a bit less), flipping once. Look for a deep golden-brown sear and clear juices. Internal temp should reach 165°F/74°C.

While the chicken rests, pour the reserved marinade into a small saucepan and bring to a simmer.

Stir in the cornstarch slurry and cook until glossy and thickened—about 1–2 minutes.

Spoon or brush this glaze over the chicken just before serving, then sprinkle with sesame seeds and green onions.

For a smoky finish, broil for 1-2 minutes after glazing.