Preheat the oven to 230°C / 450°F. Place a wire rack inside a rimmed baking sheet.
Pat the chicken wings very dry with paper towels (this is where crispiness starts).
In a large bowl, mix baking powder, salt, garlic powder, smoked paprika, and black pepper. Add wings and toss until evenly coated.
Arrange wings on the rack in a single layer with space between them.
Bake for 25 minutes, then flip all wings with tongs. Bake another 20–25 minutes until deeply golden and crisp.
While wings bake, warm BBQ sauce + butter in a small saucepan over low heat (or microwave) until melted and smooth.
Transfer hot wings to a clean bowl. Pour over the warm BBQ sauce mixture and toss quickly to coat.
For extra sticky wings, return them to the rack and bake 5 minutes more to set the glaze.
Check doneness: aim for at least 75°C / 165°F, but wings are best around 82–88°C / 180–190°F for tender bite. Serve immediately.