I put in less than Sarah probably did, because the very first time I had sweetened peanut butter I got food poisoning, and 20 years on I still have a bit of a food aversion to it. To be honest, I didn't taste it while adding, and I didn't taste the peanut butter in advance (it's a new brand Joel has started getting), so I have no idea how much sweeter I ended up making it.

I'm also not certain it needs any in the first place.