In a small mixing bowl, mix together the melted butter and peanut butter.
Add the powdered sugar to the mixture, and combine.
Stir in the crispy rice cereal, mixing everything together 'til well blended.
Shape all of the crispy dough into 1-inch peanut butter balls. Take about a tablespoonful of the peanut butter mixture and begin to roll it between your hands. Shape it into as round of a ball as you can, and place it on a baking sheet lined with wax paper. Continue rolling the rest of the dough into balls.
Add toothpicks for dipping to each peanut butter ball.
Chill the whole sheet in the fridge or freezer for about 30 minutes.
Add the chocolate to a microwave-safe measuring cup or bowl; and melt, starting at 30 seconds, then stirring every 15-20 seconds, 'til melted and smooth.
Remove the peanut butter balls from the freezer, and using the inserted toothpicks, dip every single peanut butter ball, fully immersing each one into the melted chocolate.
Place the dipped balls back onto the wax paper lined baking sheet. Remove the toothpicks, and cover over the hole by dabbing the chocolate with the end of the toothpick.
Chill the Krispie balls 'til set, probably about 15 to 20 minutes or so.
Rice Krispie peanut butter balls are best stored in between layers of wax paper, in an airtight container or festive Christmas tin, in the refrigerator for up to 2 weeks.