Chicken 65 is said to require 65 days to prepare the marinade, but this is unlikely for reasons of freshness and flavour. 
One account claims that the dish emerged as a simple meal solution for Indian soldiers in 1965. 
Another account claims that it is a dish containing 65 chilli peppers devised by an enterprising hotelier.
The name is also claimed to relate to a requirement for the meat to be from 65-day-old chickens. 
Yet another source claims that northern Indian army soldiers frequented a military canteen in Chennai. Its menus were written in Tamil, the local language. As most soldiers could not read Tamil, they made their choice by citing the number of the dish on the menu. The dish's popularity spread among the soldiers by word of mouth. They'd simply ask for "number 65"; soon, the dish became known officially as "Chicken 65".

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