Preheat the air fryer: Set it to 400°F (200°C) for 5 minutes.
This helps the skin start crisping right away.
Mix the rub: In a small bowl, combine sumac, salt, smoked paprika, garlic powder, onion powder, cumin, black pepper, and cayenne if using.
Prep the chicken: Pat the drumsticks dry with paper towels. Dry skin equals crisp skin.
Coat with oil: Drizzle the drumsticks with olive oil and toss to coat evenly.
Season generously: Sprinkle the spice blend over the chicken and rub it in to coat every side.
Arrange in the basket: Place drumsticks in a single layer in the air fryer basket. Leave a little space between them so air can circulate.
Cook: Air fry at 400°F (200°C) for 10 minutes.
Flip the drumsticks and cook another 10–12 minutes, until the skin is crisp and the internal temperature reaches 165°F (74°C).
Rest briefly: Let the chicken rest for 3 minutes to keep the juices in.
Serve: Squeeze over lemon if you like and serve with yogurt sauce, a chopped herb salad, or warm pita.