Make cake as directed in box using two 8" or 9" circle pans. Let cool.
Crush Oreos in a Ziploc bag and set aside.
Make frosting by combining butter, powdered sugar, cocoa, whipping cream and vanilla. Beat until all combined, add more powdered sugar if you want it thicker or more whipping cream if you want it thinner.
Frost cake and add crushed Oreos all over the cake (add chocolate jimmies for even more texture).
Add cinnamon candies to the front for the eyes.
Place card stock legs in the cake right before serving and enjoy!