Step 1

Preheat oven to 350 degrees, 325 degrees if using a glass pan.

Step 2

Combine the cake mix, egg and butter together. Beat until it is combined. Spray a 9 x 12 pan with cooking spray and then put the cake mix layer over the bottom. Pat it down.

Step 3

Cut the large peanut butter cups into 4 pieces. Roughly chop the Butterfingers. Spread evenly over the cake layer.

Step 4

Combine the cream cheese, vanilla and peanut butter together until combined. Add the eggs one at a time and mix them in. Add the butter. When this is all combined together add the confectionery sugar. Spread evenly over the candy bar layer.

Step 5

Bake for about 50 minutes. I used a glass pan and it took just over an hour. The mixture will be puffed up in the center when done. It will jiggly just slightly. Remove from oven and let cool.

Step 6

Melt the chocolate for 1 minute in the microwave. Add the oil. Stir until combined. Spread over the top of the cream cheese layer.