adding cocoa to a brown ale

I had some powdered cocoa lying around the house and was considering adding it to my english brown as a little additive in the secondary. There's nothing wrong with a little chocolate, right? My question is two-fold:
1. can I do this in the secondary without ruining the beer and...
2. how much should I use?

any tips are appreciated!

a few things:

yes you can add it to the secondary. it will kill the head retention though. i used some crystal 60 + wheat malt in my latest choco-stout to offset it.

i believe the best time is to add it to the end of the boil.

i dont have a clue what type of cocoa you should use. i've used hershey's before and it was terrible. now i use this specialized organic cocoa that a chick in my homebrew club has access to. everyone in our brew league says it's the only way to go. PM me if you want to know the details of it.

also, using 8 oz is the standard.

hope that helps.

yea I actually have some of the organic stuff which is what I was hoping to hear. thanks for the heads up!