Mix your pudding box with milk and and set in the fridge to set.
Process your Oreos in a food processor and set aside.
In a separate bowl, combine sweetened condensed milk, cool whip and cream cheese and beat until smooth. Add a few drops of black food coloring to make a grey layer.
Set out cups and put a scoop of Oreo crumb on the bottom of each. Then add a pudding layer, then a cream cheese layer, then more Oreo crumbs on top.
Write names and dates on your tombstone cookies and stick them in cups. Garnish cups with gummy worms and candy corn pumpkins. Enjoy!