In a large bowl or the bowl of a stand mixer, use an electric mixer to combine the peanut butter and butter until smooth and creamy. Add the powdered sugar and graham cracker crumbs. Continue to mix until a thick mixture forms.

Use a cookie scoop or a spoon to scoop out about 1 - 1 ½ tablespoons of the mixture, and roll it into a ball. Place the ball onto a parchment lined baking sheet. Repeat with the remaining peanut butter mixture. Refrigerate the peanut butter balls for 30 minutes to an hour.

Just before removing the peanut butter balls from the refrigerator, melt the chocolate. Place the chocolate in a medium bowl, and microwave on high while stirring 15 to 20 seconds until melted and smooth.

Use a fork to dip each peanut butter ball into the melted chocolate, and shake off the excess. Return the chocolate dipped peanut balls to the baking sheet. Drizzle the dipped balls with excess chocolate, then return to the refrigerator to set for at least 30 minutes.

Serve, and store leftovers in the refrigerator for up to 5 days.