In a large bowl, combine the chicken pieces with 1/4 cup of soy sauce, 1/4 cup of Shaoxing wine, and 2 tablespoons of sesame oil. Mix well to coat the chicken. Marinate for at least 6 hours, or ideally overnight in the refrigerator.

Before cooking, take the chicken out of the refrigerator and let it sit at room temperature for about 30 minutes to take the chill off.

Heat the remaining 6 tablespoons of sesame oil in a wok or a heavy clay pot over medium-high heat until it is sizzling hot. Add the smashed garlic cloves and ginger slices and stir-fry until fragrant, about 1-2 minutes. Be careful not to burn the garlic.

Add the marinated chicken pieces to the wok, spreading them out in a single layer if possible. Sear the chicken for 3-5 minutes until browned on all sides.

Pour in the remaining 1/4 cup soy sauce and 1/4 cup Shaoxing wine. If using, add the sugar and chili flakes. Bring the mixture to a simmer, then reduce the heat to medium-low, cover, and let it braise for 15-20 minutes, or until the chicken is cooked through and tender, stirring occasionally.

Remove the lid and increase the heat to medium-high. Cook for another 5-10 minutes, stirring frequently, to reduce the sauce until it thickens slightly and coats the chicken.

Stir in the fresh basil leaves until they wilt, about 30 seconds.

Serve immediately with steamed white rice.