The melted peanut butter likes to harden pretty quickly on the cold cookie balls. The easiest ways to coat the cookie balls is to stick a toothpick in the top center and roll the cookie ball in the peanut butter. OR place the cookie ball on a fork, hold the fork over the peanut butter bowl, and use a spoon to drizzle peanut butter around the sides. Tap the fork on the edge of the bowl to knock off excess peanut butter. Use a knife to slide the cookie ball off the fork.