Line a rimmed baking sheet with foil and grease well with cooking spray.
Add sauce ingredients (except cornstarch) to a small pot and whisk together. Cook on the stove over medium heat just until the butter is melted. Turn off the heat.
Separate the wing’s drumstick from the thinner parts of the wings using kitchen shears (if applicable). Remove any excess feathers. Pat chicken wings dry with a paper towel.
To a large bowl add 3 tablespoons of the sauce, onion powder, garlic powder, salt, pepper and cornstarch. Mix together until the cornstarch has dissolved.
Add the chicken wings into the bowl. Massage the wings with the sauce mixture until well coated.
Let wings marinade for 15 minutes at room temperature, as you preheat the oven to 400°F. Be sure the oven rack is in the center position in the oven.
Place wings on the greased pan, in a single layer, and bake for 40 minutes until the chicken is crispy and reaches an internal temperature of at least 165°F (it’s ok if it’s higher).
While the wings bake, continue to simmer the sauce on medium-low heat, for 15 minutes. Mix in the cornstarch slurry and cook on medium-high for 30-60 seconds, stirring frequently, until thickened. Immediately, turn off the heat once it begins to thicken. Set aside to cool.
Once the wings are taken out of the oven, increase the oven temperature to 425°F.
Set aside ⅓ cup of sauce for later. Using the remaining sauce, brush it over the cooked wing. Return to the oven for 8 minutes to become more crispy.
When the wings are finished cooking, allow to cool for 10 minutes. Transfer to a bowl and toss with the ⅓ cup sauce that was set aside.
Garnish with a sprinkle of sesame seeds and sliced scallions.