Add the peanut butter, butter, and vanilla to a large bowl or stand mixer and cream together for 30 seconds.
Sift 3 cups of the powdered sugar into the bowl and beat until smooth. If the mixtture is still too soft, beat in an additional 1/2 cup. The mixture should stick together but not be sticky, moore of a set fudge texture.
Chill the mixture in the refrigerator for 30 minutes.
Line a cookie sheet with parchment paper and portion the peanut butter mixture out with a medium cookie scoop and roll into balls. Place them on the cookie sheet and chill in the freezer for 20 to 30 minutes.
Just before removing the balls from the freezer, melt the chocolate melting wafers in a wide glass on 30-second intervals, stirring between each, until fully melted.
Use a toothpick to spear the balls and dip them in the melted chocolate. Use a fork to help remove the toothpick from the ball and place back on the parchment paper.
Use your finger or a paring knife to lightly cover the hole from the toothpick.
Allow to set until the chocolate hardens.