Divide the chicken into 3 equal portions (1 lb each). For Hara Masala: blend coriander, mint, green chilies with yogurt, ginger garlic paste, cumin, salt, lemon juice, and oil into a smooth paste. Coat one portion and marinate.
For Spicy Masala: whisk yogurt with red chili powder, ginger garlic paste, turmeric, garam masala, salt, lemon juice, and oil. Coat the second portion and marinate.
For Malai Boti: whisk cream, hung curd, cashew paste, white pepper, green chili paste, cardamom, salt, and oil until smooth. Coat the third portion and marinate.
Cover all three and refrigerate for at least 2 hours, or overnight for best flavour. (Optional coal smoke: heat charcoal until red-hot, place in a small bowl in the centre of the chicken, drizzle with ghee, cover tightly for 10 minutes.)
Thread each marinade onto separate skewers. Cook on a hot grill pan over medium-high heat for 4-5 minutes per side until cooked through and charred at the edges. Cook in batches — do not crowd the pan.
Brush with melted butter, rest for 2-3 minutes, and serve hot with onion rings, lemon wedges, and mint chutney.