In a grinder, add cilantro leaves, mint leaves and green chillies. Grind them on high speed for a few seconds till you achieve a smooth paste.
In a large bowl add this paste along with curd, turmeric powder, red chilli powder, garam masala powder, dry mango powder, cumin powder, salt and pepper. Mix well and then add the chicken pieces to it.
Make sure that the chicken pieces have an even coating of this mixture. Keep it aside and let it marinate for a minimum of 30 minutes.
Heat the griller now and drizzle oil over it. Place the marinated chicken pieces on it and grill them till they turn brown from all the sides.
Your Hariyali chicken tikka is now ready to tuck in. Remove from the griller and serve hot along with some tangy chutney and sliced onions.