My 1st firecracker...any advice/warnings

http://www.waytoomany.com/forum/viewtopic.php?t=4990

Here there is a guy saying to use Jif and skippy o.o so yeah

I just made 4 fire crackers with Jif peanut butter and well It worked I just finished eating the biggest cracker like 10 min ago. There all gone and already I'm feeling something so yeah Jif works!!