I just tried one not too long ago. Brooklyn Beer or something? I’d have to look into it now. But it wasn’t too bad.
Here it is:
http://www.brooklynbrewery.com/beer/?beer=black_chocolate_stout
I’m sure you’ll be ok…mine seem to be kid proof 
And don’t buy just anything!! Seriously…you can look on Amazon but if you want to ask questions before you buy, feel free to email me (hit the email link at the bottom of the post). I’d be more than happy to give you advice and suggestions, if you’d like. Most of what’s out there is pretty much crap…the kits tend to have you use TONS of sugar which makes it taste really nasty; better than Budweiser, but not as good as it can be if you know what I mean. If you buy the stuff separately, you get a much better product. But seriously, email me if you have questions.
nah, after my initial “ooh, brew my own beer!” thought, it occurred to me that I don’t actually have any room in my tiny wee 1 bedroom flat to put a brewery.
One of the aroma and flavour attributes we score Doom Bar samples on is chocolate. It typically gets a middling score (so not as much chocolate as a good Merlot!) I presume it comes from the roast malt they use in the brew.