Preheat your oven to 375°F (190°C).
In a bowl, combine the chopped apple, scallions, ginger slices, and garlic.
Heat the olive oil in a large skillet over medium-high heat. Add the apple, scallions, ginger, and garlic mixture to the skillet and cook for about 3-4 minutes, until fragrant and slightly softened.
Stir in the apple cider vinegar, fish sauce (if using), coconut aminos, and toasted sesame oil (if using). Let the mixture simmer for about 2 minutes to meld the flavors.
Season the chicken thighs with sea salt and black pepper (if using).
Place the chicken thighs in a baking dish and pour the ginger glaze mixture over the top, ensuring the chicken is well-coated.
Transfer the baking dish to the preheated oven and roast for 30-35 minutes, or until the chicken thighs are cooked through and tender. Baste the chicken with the glaze halfway through cooking for extra flavor.
Once done, let the chicken rest for a few minutes before serving.