In a small bowl whisk together the honey, rice vinegar, soy sauce, hoisin sauce, 1 teaspoon cornstarch, toasted sesame oil and red pepper flakes (if using).

Pat the chicken thighs dry with paper towels and put them in a medium bowl. Season all over with the salt. Sprinkle the 1/4 cup cornstarch over the chicken and toss with your hands until evenly coated, separating any pieces that are stuck together.

Heat 2 tablespoons of the oil in a wok or 12-inch nonstick frying pan over medium-high heat until shimmering. Add half of the chicken and spread it into an even layer. Cook undisturbed until golden-brown on the bottom, 4 to 5 minutes. Flip and cook undisturbed until the second side is browned and the chicken is cooked through, 4 to 5 minutes more; a piece should read 165°F on a food thermometer. Move the chicken to a plate.

Add the remaining 1 tablespoon oil to the pan and cook the rest of the chicken the same way, 4 to 5 minutes a side, until it is cooked through and reads 165°F. Leave this chicken in the pan. Add the garlic and ginger and cook until the garlic is fragrant and lightly golden-brown, about 30 seconds.

Return the first batch of chicken and any juices that collected on the plate to the pan. Whisk the sauce again and pour it in. Gently toss until the sauce thickens, turns glossy and coats the chicken, about 2 minutes.

Top with the sliced scallion and sesame seeds if using. Serve right away.