Seriously, we had a Iron Brewer competition in our club. That was the ingredient I was given. I put four ounces in the mash and soaked some in vodka and added it to the finished beer to adjust the flavor.
Unfortunately, I am not a fan of peanut butter. So I didn't care for the beer. But my neighbors liked it.
I ordered a jar on amazon, if you added it onto an order over $25 you get free shipping or something. I'm planning to make a chocolate porter & add this. Planning to use the Choconut Porter recipe that's on here, less the nut extract. Also only doing 2.5g of it for a test!