Preheat your oven to 400°F (200°C). In a large mixing bowl, combine the chicken wings and drumettes with baking powder and kosher salt. Toss until fully coated.
Place the wings in a single layer on a baking sheet lined with parchment paper. Bake for 40-45 minutes, flipping halfway through, until golden brown and crispy.
In a medium saucepan, combine pineapple juice, rice vinegar, brown sugar, ketchup, and soy sauce. Whisk over medium heat until it comes to a gentle boil.
Mix cornstarch with water to create a slurry. Once the sauce is boiling, slowly whisk in the cornstarch mixture and continue cooking for 2-3 minutes until thickened.
Once wings are done, remove from the oven and place in a large bowl. Pour the sauce over the wings and toss until evenly coated.
Transfer the glazed wings to a serving platter and serve hot. Garnish with chopped green onions or sesame seeds if desired.