1. Preheat the oven to 350°F and grease two 9-inch round cake pans.

2. In a large bowl, combine the chocolate cake mix, eggs, vegetable oil, and water. Mix until smooth.

3. Divide the batter evenly between the prepared pans and bake for 25 to 30 minutes, or until a toothpick inserted in the center comes out clean.

4. Let the cake layers cool completely in the pans for 10 minutes, then transfer to a wire rack.

5. In a mixing bowl, beat the softened cream cheese until smooth.

6. Add 1 cup peanut butter and powdered sugar, then mix until creamy and fully combined.

7. Fold in the whipped topping until the filling is light and fluffy.

8. Place one cake layer on a serving plate and spread half of the peanut butter filling over the top.

9. Sprinkle half of the crushed Butterfinger candy over the filling.

10. Add the second cake layer and spread the remaining filling on top.

11. Heat the heavy cream until hot but not boiling, then pour it over the chocolate chips. Let sit for 2 minutes and stir until smooth.

12. Pour the chocolate ganache over the top of the cake, letting it drip down the sides.

13. Decorate with the remaining crushed Butterfinger candy and dollops or drizzles of 1/4 cup peanut butter.

14. Chill the cake for at least 1 to 2 hours before slicing and serving.