Ok, so you should let this cool for an hour or two in the fridge after making it, but it seriously takes less than 10 minutes to make and it's some of the best pb fudge I've had :)
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2 cups creamy peanut butter (about 2/3 of a small jar)
1 lb butter (meaning one regular rectangular box of butter containing 4 sticks - no margarine)
2 teaspoons vanilla extract (obviously you'll have to buy the whole jar of vanilla extract, but that's ok because it's something you should have for other recipes anyway)
2 lbs powdered sugar
Put butter and peanut butter together in a medium sized microwave-safe bowl (if I were you, I'd hit thrift stores and buy the old fashioned white glass mixing bowls for microwave use. Who cares if they are avocado green; they last forever and they don't melt in the microwave, plus you can even bake in them if you need to. Just make sure they don't have any metallic designs on them as back then metallic designs were made with actual metal, which is not microwave safe unless you want your microwave looking like a sparkler).
Microwave on high for two minutes. Stir well. Microwave on high for another two minutes. Remove and stir well again.
At this point you have two options - you can use a stand mixer or you can stir it by hand.
If you are using a mixer, dump the melted pb and butter into your mixer's bowl, stir in the vanilla, and turn onto low speed. Slowly add in powdered sugar 1/4-1/2 cup at a time. If you add it in all at once or if your mixer is on a higher speed, the powdered sugar is so fine that it will be blown out of the bowl and will coat you and your kitchen in a lovely covering of white. I suppose if you're desperate for snow, you could try this, but it's a pain in the butt to clean up, plus then you don't have pb fudge to eat at the end.
If you are stirring it by hand, stir in the vanilla, then stir in the powdered sugar about 1/2 c. at a time. Or just pour a bit in at a time. You don't have to measure it; it will just make it easier to stir in this way.
Whichever way you mixed it together, spray a 9x13 cake pan with pam (this is a normal sized cake pan. If you don't have one,
it really doesn't matter if you use another size; it will just make your
fudge either thinner or thicker than mine usually is). Scrape the mixture out of the bowl and into the cake pan. Press it evenly into the pan.
Chill in the refrigerator for at least an hour, probably two. Cut into pieces and eat :) Store any leftovers in the fridge as it melts a bit in warmer places.
*Recipe by Alton Brown, found on foodnetwork.com