In the soy sauce, rice vinegar, garlic and five spice powder, toss the chicken wings. Let marinate for 2 hours.

Preheat oven to 400 degrees. Set a wire rack inside a lined rimmed baking sheet.

In a ziplock bag, combine baking powder and potato starch or cornstarch. Remove chicken wings from the marinade and place in the ziplock bag.

Close the bag and shake until the wings are thoroughly coated in marinade.

On the prepared rack, lay the wings and bake for 45 minutes, until golden brown and crispy.

Season with a generous sprinkling of five spice powder, salt and pepper, if desired.

Garnish with green onions and serve hot.