Pat chicken pieces dry with paper towels. In a medium bowl, drizzle chicken with 2 tablespoons vegetable oil, then sprinkle with 1/2 teaspoon salt and 1/4 teaspoon black pepper. Toss to coat evenly and set aside.

In a liquid measuring cup, combine minced garlic, 1/3 cup honey, 1/3 cup chicken stock, 1 tablespoon rice vinegar, 1 tablespoon light soy sauce, and optional 1/2 teaspoon chilli flakes. Whisk until well combined. In a separate small bowl, whisk 2 tablespoons cornstarch with 4 tablespoons cold water until smooth to form a slurry. Set both aside.

Heat a large 10 to 12 inch skillet over medium-high heat with additional vegetable oil and 1 tablespoon unsalted butter. Sear chicken in batches of 3 to 4 pieces without overcrowding the pan for 3 to 4 minutes per side, until deep golden-brown with slightly darker edges and cooked through (internal temperature of 165°F/74°C). Transfer cooked chicken to a clean plate and set aside.

Reduce heat to medium-low. Pour the prepared honey garlic sauce into the skillet, bringing it to a gentle simmer with small bubbles breaking the surface while stirring continuously for about 1 minute.

Re-whisk the cornstarch slurry thoroughly, then slowly pour it into the simmering sauce in a thin stream, stirring constantly. The sauce will thicken within 30 to 60 seconds into a glossy glaze that coats the back of a spoon and drips off slowly. If too thick, add 1 tablespoon chicken stock; if too thin, simmer another 30 seconds.

Return all cooked chicken pieces to the skillet, tossing gently but thoroughly to coat every piece in the sticky glaze. Simmer for 1 to 2 minutes to meld flavors.

Transfer Honey Garlic Chicken to a serving platter or individual bowls. Garnish generously with finely chopped fresh parsley. Serve immediately over cooked rice.