Prep the paneer and veggies: Pat paneer cubes dry with a paper towel. Cut peppers and onions into bite-sized pieces. Drying helps the marinade stick and improves browning.

Roast the gram flour: In a small dry pan over medium heat, toast besan for 2–3 minutes until it smells nutty and turns slightly deeper in color. Set aside to cool. This helps the marinade cling and adds body.

Make the marinade: In a large bowl, mix yogurt, ginger-garlic paste, lemon juice, mustard oil, roasted besan, chili powder, garam masala, cumin, coriander, turmeric, kasuri methi, salt, and pepper. Stir until smooth and thick. If it looks runny, add 1–2 teaspoons more besan.

Coat the paneer and veggies: Add paneer, peppers, and onion to the bowl. Gently fold with a spatula to coat without breaking the paneer. If using, add chopped green chilies and herbs.

Marinate: Cover and refrigerate for at least 30 minutes, ideally 2 hours. For best flavor, marinate up to 8 hours. Do not go overnight with fresh paneer or it can soften too much.

Preheat the air fryer: Set to 400°F (200°C) for 3–5 minutes. Lightly brush or spray the basket with oil to prevent sticking.

Arrange in the basket: Place marinated paneer and veggies in a single layer with a little space between pieces. Avoid overcrowding. Reserve extra marinade for the next batch.

Air fry: Cook at 380–390°F (193–199°C) for 9–12 minutes, shaking or flipping halfway. Brush lightly with oil at the 6–7 minute mark for better color and moisture. Cook until edges char and the marinade looks set.

Finish and serve: Transfer to a platter, sprinkle with chaat masala, and garnish with cilantro. Serve hot with mint-cilantro chutney, lemon wedges, and sliced onions.

Batch cook as needed: Repeat with remaining mixture. Keep cooked bites warm in a 200°F (95°C) oven while you finish the rest.