Line a baking sheet with wax paper. Set aside.
Use an electric hand mixer to cream together the unsalted butter, creamy peanut butter, and vanilla extract.
Add the powdered sugar about ¼ cup at a time, mixing between each addition.
Use a wooden spoon to hand mix the Rice Krispie cereal into the bowl. Portion the dough into 1 Tbsp portions and roll into a ball in your hand. Place the Peanut Butter Balls on the wax paper lined baking sheet and place in the freezer for about 10 minutes.
When the dough is almost done freezing, melt the chocolate chips. To do so, place the chocolate chips and the vegetable oil in a microwave safe bowl and microwave for 30 second increments, stirring between each set, until completely melted.
Remove the dough from the freezer. Drop the peanut butter balls in the melted chocolate, then place the balls back on the wax paper lined baking sheet.
Place the cookie sheet back in the freezer for another 5-10 minutes until the chocolate hardens. Then serve and enjoy!