Preheat oven Preheat oven to 425F (220C). Place wire rack inside rimmed sheet pan. Let the oven fully preheat for at least 10 minutes after the signal before putting wings in.
Dry the wings Pat chicken wings completely dry with paper towels - all surfaces, including the underside and any folds. This is the most important step for crispy oven chicken wings. Surface moisture becomes steam in the oven and prevents the skin from crisping. Take more time on this than feels necessary.
Season In a large bowl, mix baking powder, salt, garlic powder, smoked paprika, onion powder, black pepper, and cayenne. Add wings and toss until every surface is evenly coated. Drizzle avocado oil over the wings and toss again to coat lightly. The oil helps with browning and helps the seasoning adhere.
Arrange on rack Place wings skin side up on the wire rack in a single layer with a small gap between each piece. Do not crowd them - touching wings trap steam between them and the skin where they contact will not crisp. Work in two batches if needed.
Bake Bake at 425F for 25 minutes. Flip each wing over. Return to the oven for another 18 to 20 minutes until the skin is deeply golden and visibly crunchy. Total bake time is 43 to 45 minutes.
Check temperature Check the internal temperature at the thickest part of the largest wing - not touching the bone. Wings are safe at 165F. For best texture, push to 175F - at this range the connective tissue breaks down and the meat pulls cleanly from the bone.
Optional broil For extra crunch, switch the broiler to high for 2 to 3 minutes after baking. Watch closely - at this stage the wings go from perfect to burnt quickly. This step is optional if the skin is already as crispy as you want it.
Sauce and serve Remove wings from oven. If tossing in sauce, do it now in a large bowl just before serving - sauce goes on after baking, never before. Serve crispy oven chicken wings immediately while the skin is at peak crunch.