Adjust oven rack to the middle position and preheat oven to 450°F (218°C). Line a large baking sheet with foil. Set a wire rack inside and coat with vegetable oil. Thoroughly dry chicken wings between paper towels.
In a large bowl, whisk together baking powder, salt and pepper. Add wings to the bowl and evenly coat the surface with the baking powder mixture. Evenly space the wings on the wire rack. Bake for 20 minutes. Flip and bake for 15 minutes. Flip and bake until skin is golden brown and crisp, 15 minutes. Remove the wings from the oven and set aside.
In a medium sized saucepan whisk together soy sauce,3/4 cup water, honey, rice vinegar, mirin, sesame oil, ginger and garlic. Bring sauce to a boil over medium-high heat and cook for 1 minute. Meanwhile, in a small bowl, whisk together cornstarch and 2 tablespoons water. Add cornstarch slurry into the boiling sauce, whisk to combine. Continuously stir until sauce is thickened, coating the back of a spoon, 30 to 60 seconds.
Toss wings in enough teriyaki sauce to coat, or serve sauce on the side for dipping. Serve immediately.