Marinate: toss chicken with ginger garlic paste, lemon juice, turmeric, salt; rest 15 min room temp (or up to 1 hr in fridge).
Batter: whisk besan, rice flour, ajwain, chili powder, garam masala, cumin, baking soda, salt; add water 1 tbsp at a time to thick pancake-batter consistency.
Coat chicken fully; rest coated pieces 5 minutes.
Preheat to 400°F (200°C); oil the basket; arrange in a single layer; brush tops with oil.
Air fry 10 min, flip, 8–10 min more at 400°F to 165°F (74°C) internal.
Serve hot with mint chutney, lemon wedges, onion rings, cilantro.