In a blender or food processor, crush the chocolate sandwich cookies until they are fine crumbs. Set aside. This can be done up to three days in advance.

In a large bowl, whisk together the chocolate pudding mix and milk according to package instruction until smooth and creamy. Set aside, covered in plastic wrap in the fridge until ready to use. This can also be done up to three days in advance.

In a large bowl with an electric hand mixer, a whisk, or using a stand mixer with the whisk attachment, whip the heavy cream until frothy. Gradually add in the sugar, shake a little in at a time, and add vanilla extract as the whipped cream becomes thicker.

Whip the cream until it becomes very thick, holding a stiff peak. Do not overwhip, you'll make butter. Once the whipped cream is thick and stiff, set aside covered with plastic wrap in the fridge until ready to assemble.

Take half the pudding and half of the whipped cream in a medium-sized bowl and gently fold them together using a spoon.

In your serving dishes, layer small amounts of the pudding, the pudding-whipped cream mix, and the crushed cookie crumbs. Add candies and sprinkles in layers as desired. Repeat until the serving dish is full, ending on a layer of the crushed cookies.

Take the rest of the whipped cream and put it into a piping bag with a very small round piping tip or zip-top bag and snip a small hole in the corner. Make sure the top of the zip-top bag (if using) is closed fully before piping small ghosts on the top of the cookie 'dirt'. Add tombstone candies.

Serve chilled, or keep in the fridge until ready to serve.