Combine soy sauce, brown sugar, honey, Miran, apple juice, sesame oil, ginger, and garlic in a saucepan. Heat until sugar dissolves (about 5 minutes).
Pour the sauce into a dish with the chicken. Cover and refrigerate allowing it to marinate for a minimum of 30 minutes (preferably 2-4 hours).
Once the chicken is finished marinating remove it and pat dry with a paper towel.
Heat olive oil in a large skillet. Add the chicken thighs and sear on both sides. (about 2 minutes per side) Remove and place in a single layer in an oven-proof baking dish.
Whisk the cold water and cornstarch together until fully mixed with no lumps present.
Pour the marinade into a saucepan and heat until boiling. Gradually whisk in the cornstarch slurry. Reduce the heat to medium and simmer until the sauce thickens. Whisk continually.
Pour over the chicken.
Place in the oven and bake uncovered at 375º F for 20-25 minutes or until chicken reaches an internal temperature of 165º F.
Garnish with thinly sliced green onion and sesame seeds.