In a large bowl, combine yogurt, ginger-garlic paste, red chili powder, garam masala, lemon juice, and salt to prepare the marinade.
Add the paneer cubes and gently coat them with the marinade without breaking them.
Cover and refrigerate for 30–60 minutes to allow the flavors to develop.
Thread the marinated paneer cubes onto skewers, alternating with bell peppers and onions if desired.
Preheat the oven or grill to 200°C (390°F).
Grill the skewers for 10–12 minutes, turning occasionally and brushing with butter or oil until lightly golden.
Remove from the grill and garnish with chopped coriander leaves.
Serve hot with mint chutney, onion rings, and fresh lemon wedges.