Combine the peanut butter and softened butter in a medium mixing bowl. Using an electric hand mixer set to medium speed, beat the mixture until uniformly smooth and incorporated.
Pour in the vanilla extract and mix briefly until well blended.
Gradually incorporate the powdered sugar in portions, beating on low speed after each addition. Pause occasionally to scrape down the sides of the bowl to ensure even mixing.
Fold in the crushed graham cracker crumbs and the chopped Butterfinger bits until fully integrated into the dough.
Line a baking sheet with parchment paper. Scoop out portions of the mixture—approximately 1 to 1½ tablespoons each—and roll them between your palms to form compact, uniform balls. Arrange them evenly on the prepared tray.
Transfer the tray to the freezer and chill the balls for approximately 30 minutes, or until they are firm to the touch.