Whisk ¼ cup honey, 3 tablespoons rice vinegar, 2 tablespoons soy sauce, 2 tablespoons hoisin sauce, 1 teaspoon of the cornstarch, 1 teaspoon toasted sesame oil, and ½ teaspoon red pepper flakes if using together in a small bowl.

Pat 1 ½ to 2 pounds chopped boneless, skinless chicken thighs dry with paper towels. Place in a medium bowl and season all over with ½ teaspoon kosher salt. Sprinkle the remaining ¼ 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 neutral oil in a wok or 12-inch nonstick frying pan over medium-high heat until shimmering. Add half of the chicken and spread into an even layer. Cook undisturbed until golden-brown on the bottom, 4 to 5 minutes. Flip and cook undisturbed until the chicken is browned on the second side and cooked through, 4 to 5 minutes more. Transfer to a plate.

Add the remaining 1 tablespoon oil to the pan and repeat cooking the remaining chicken; keep this chicken in the pan. Add 2 minced garlic cloves and 2 teaspoons minced peeled ginger. Cook until the garlic is fragrant and lightly golden-brown, about 30 seconds.

Return the reserved chicken and any accumulated juices on the plate to the pan. Re-whisk the sauce and then pour into the pan. Gently toss until the sauce thickens, is glossy, and coats the chicken, about 2 minutes. Garnish with 1 thinly sliced medium scallion and 1 teaspoon toasted sesame seeds if using.