Grind the onion, garlic, ginger and lemon grass to a paste. Keep aside.
Take the chicken in a bowl.
Add the ground paste.
Add coriander powder, chilli powder,turmeric powder,cumin powder, salt, sugar, meat masala, corn flour, egg and curry leaves. Mix well.
Refrigerate for 8 hours at least.
Take the chicken out of fridge and bring to room temperature.
Heat oil for deep frying.
Carefully drop the chicken pieces, along with coating, into the oil and fry till evenly brown on all sides.
Drain onto an absorbent paper.