Bake the cake, according to package directions, in a 9x13 inch baking pan.

Allow the cake to cool completely, and use a straw to poke holes throughout the cake.

In a medium mixing bowl, whisk together chocolate pudding mix and milk.

Quickly pour this over the cake before the pudding begins to set so that it will fill the holes poked in the cake.

Next, blitz the Oreo cookies to crumbs in a food processor.

Sprinkle those over the pudding topped cake.

Move this to the refrigerator to chill for 1 hour.

For the frosting, in a medium mixing bowl, beat together the butter and powdered sugar, slowly adding the vanilla, green gel color, and splashes of milk, until frosting forms.

Add the frosting to a piping bag and snip off the very tip.

Use the frosting to decorate the cake with pumpkin "vines."

Place your pumpkin candies on top.

Enjoy!