Line a baking sheet with waxed paper and set aside.
Mix peanut butter, butter and vanilla together in a large bowl.
Slowly add one cup of powdered sugar to the creamy mixture, mixing well each time. *Note — I do not sift my powdered sugar! I just scoop out 1 cup full and dump it in my bowl.*
By the time you get to the third cup of powdered sugar, the mixture will become very difficult to stir with a spoon. Take your rings off and start mixing with your hands.
Once all of the powdered sugar is incorporated into the peanut butter mixture, you can start making your balls. Simply pinch off a small amount and roll between your hands to form a small ball. Place the peanut butter balls on the prepared cookie sheet with waxed paper.
Once you have made all of your balls, melt your chocolate. My favorite way to do this is in the double boiler, but if you don’t have one, you can simply put a metal or glass bowl on top of a saucepan with about an inch of water in it. As the water in the saucepan begins to heat up, the steam will heat up your bowl and start melting your chocolate. Be sure to add the shortening to your chocolate – this will make covering your peanut butter balls with chocolate a lot easier.
One at a time, drop your peanut butter balls into the melted chocolate. Lift the ball out of the chocolate with a fork and then transfer it to the waxed paper.
Once all of your peanut butter balls are coated, put the cookie sheet in the fridge for 15-30 minutes. This will ensure the chocolate coating is completely hardened.