This is the second novelty beer that I'm making for this year's Vice City, so I was free to go a little crazy with ingredients. I wouldn't ever make a batch of this myself because I can't imagine trying to drink 5 gallons of a chocolate peanut butter stout. A few months ago I got a growler of a similar beer and it was hard to work my way through just that much!
That's the fun of these novelty beers, though. I can experiment with beers that I'd otherwise never brew, and I don't have to worry about drinking the results.
This recipe started off as Jamil's American Stout recipe from Brewing Classic Styles. I added a bag of lactose to push it closer to a sweet stout, since I thought a sweeter beer would mesh better with the chocolate and peanut butter. And to boost that sweetness I went with a lower-attenuating American yeast: Wyeast Northwest Ale.
To get chocolate into the beer I went with cocoa powder. Others recommended unsweetened baking chocolate, but I didn't want to introduce any more oil into the beer. For the peanut butter I got 8oz of fresh ground peanuts from the store. I then spread out the fresh peanut butter into a thin layer and covered it with paper towels. I replaced the towels as they soaked up the oil. I did this on and off for several weeks, eventually ending up with a mostly de-oiled peanut butter.
I kinda stumbled my way through this one due to baby-induced sleep deprivation. I even forgot to add the 5-minute hop addition, which I'm not overly concerned about. This isn't a beer that needs additional hop flavor and that last hop addition was a holdover from the original recipe.
For reasons that I can't quite explain the OG ended up 5 points high, coming in at almost 1.078. My efficiency was a bit higher than expected, but not high enough to explain the jump in OG. Weird, but again not something I'm going to worry about. The other nice thing about novelty beers is that you don't have to sweat the details quite as much.