Add the peanut butter, butter, and vanilla extract to the bowl of a stand mixer fitted with the paddle attachment. Beat on medium speed until combined. 

Next add the powdered sugar and mix to combine – scrape down the sides of the bowl as needed. 

With the mixer on low speed, slowly add the rice krispies. Mix just until they are incorporated. 

Scoop out 1 tablespoon size portions and place them on a parchment or silpat lined baking sheet. Chill in the fridge for 20 minutes. 

When the peanut butter balls have set slightly, roll them into smooth balls. Then place them in the freezer to chill for 20 minutes, or until very cold and stiff. 

Melt the chocolate candy coating according to the package directions. Working one at a time, dip a peanut butter ball into the chocolate. Remove the ball with a fork, allowing excess chocolate to drip back into the bowl. Then place the chocolate coated peanut butter ball back onto the parchment paper. Repeat until all of the peanut butter balls have been coated with chocolate. 

(Optional) Place any leftover chocolate into a small ziploc bag and cut off the tip of one corner. Drizzle the chocolate over the peanut butter balls. 

Place the peanut butter balls into the fridge to chill until the chocolate is set– about 10 minutes.