Mix all marinade ingredients in a bowl: yoghurt, besan, ginger-garlic paste, all spices, lemon juice, oil, and salt. Whisk well until smooth.
Add paneer cubes, capsicum, onion, and tomato to the marinade. Mix gently to coat everything. Cover and refrigerate for at least 30 minutes.
Thread the marinated paneer and vegetables alternately onto skewers. If using wooden skewers, soak them in water for 20 minutes first.
Grill on high heat, turning every 2-3 minutes, until nicely charred on all sides — about 10 minutes total. OR bake at 220°C for 15 minutes then broil for 3 minutes.
Remove from skewers. Squeeze lemon juice over the top, sprinkle chaat masala, and serve immediately with mint chutney.