Preheat the pellet grill or Traeger to 225°F. Pat the chicken wings dry with paper towels.
Mix the baking powder, barbecue spice blend, and kosher salt together.
Sprinkle the mixture over the wings on a sheet pan or in a bowl and toss until every piece is evenly coated.
Place the wings on a wire rack over a sheet pan and spread them out so they are not crowded or touching. If you have time, let them rest in the fridge for 4 to 24 hours so the skin can dry out for optimal crispiness.
Place the wings directly on the grill grates in a single layer. Smoke for 45 to 60 minutes, or until the wings reach about 150°F to 160°F internal temperature and the skin looks set.
Increase the grill temperature to 400°F and flip the wings over so they cook evenly.
Continue cooking until the skin is crisp and the thickest pieces reach at least 165°F. For better wing texture, cook them closer to 175°F to 185°F.
Pull the wings from the smoker and rest them for 5 minutes. Serve them dry with dipping sauce on the side, or toss them lightly with warm sauce after the skin has crisped.