Line a rimmed baking sheet with aluminum foil and set a wire rack inside.
Carefully dry chicken wings with paper towels.
In a large bowl, combine 1 pound wings with 1 teaspoon baking powder and 1 teaspoon salt, and toss until thoroughly and evenly coated.
Place on rack, leaving a slight space between each wing. Repeat with remaining wings, baking powder, and salt.
Refrigerate baking sheet with wings, uncovered, at least 8 hours and up to 24 hours.
When ready to cook, adjust oven rack to upper-middle position and preheat oven to 450°F (230°C).
Cook chicken wings for 20 minutes.
Flip wings and continue to cook until crisp and golden brown, 15 to 30 minutes longer, flipping a few more times towards the end.
Meanwhile, in a medium saucepan, combine brown sugar, miso, fish sauce, rice vinegar, and garlic, and bring to a simmer over medium heat.
Stir until sugar dissolves and simmer until mixture thickens to a glaze-like consistency that coats the back of a spoon, 5 to 10 minutes.
Remove from heat and set aside.
Transfer wings to a large bowl and toss with prepared sauce until coated evenly.
Sprinkle with sesame seeds and toss to coat.
Serve wings immediately.
