Westfall Chicken

To get the Chicken as a companion pet...

1) Buy special chicken feed from William Saldean (in front of the house).
2) L click on one chicken (it is yellow/neutral).
3) Cluck at the chicken repeatedly. You can simply emote chicken to cluck at the chicken, but I suggest doing a macro as you will need to cluck several times (anywhere from 25 to 50 times or more).
4) You will continue to cluck until the chicken goes from yellow/neutral to green/friendly.
5) Once green/friendly, the chicken offers a quest asking for the special chicken feed (that you should have readily available in your bags).
6) Feed the chicken...quest complete.
7) The chicken will lay an egg...pick it up.
8) R click the egg in your bag...gratz on your new chicken!

I'am very curious how someone found out how to get this pet so long ago? I can't imagine someone in the game thinking "maybe if I cluck at the chicken..." etc.

As of the latest PTR build (9658), you can also purchase the Special Chicken Feed from William Saldean in Brill for Horde characters interested in obtaining the Westfall Chicken. Obtaining the pet is the same the Alliance would... basically, spam the /chicken emote at a nearby chicken, give it some feed, then loot the egg.