In a medium bowl, cream together the peanut butter and butter until smooth. Mix in the powdered sugar and vanilla until fully incorporated.
Add in the Rice Krispies and gently mix in by hand until uniformly distributed.
Line a baking sheet with wax paper or parchment paper. Using a medium cookie scoop, scoop the peanut butter mixture onto the prepared baking sheet and place in the freezer for around 30 minutes.
Remove from the freezer and roll into balls. Return to the freezer until they have hardened.
In a small microwave safe bowl, microwave the chocolate chips and coconut oil in 30 second intervals, mixing until smooth.
Place a toothpick into a frozen peanut butter ball. Dip into the melted chocolate. Return to the baking sheet and remove the toothpick. Using a butter knife, smooth the toothpick mark off.
Allow the chocolate to harden before eating, either at room temperature or in the fridge.