Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.

In a large mixing bowl, cream together the softened butter, granulated sugar, and brown sugar using an electric mixer until light and fluffy.

Add the eggs one at a time, mixing well after each addition, then stir in the vanilla extract.

In a separate bowl, whisk together the all-purpose flour, black cocoa powder, baking soda, and salt.

Gradually add the dry ingredients to the wet ingredients, mixing until just combined.

Scoop tablespoon-sized amounts of dough and place them onto the prepared baking sheet, leaving space for spreading.

Bake in the preheated oven for 10-12 minutes or until the edges are set and the centers are slightly soft.

Once baked, remove the cookies from the oven and let them cool on the baking sheet for 5 minutes before transferring them to a cooling rack.

In a separate bowl, prepare the chocolate pudding by whisking together the pudding mix and milk until thickened.

Fold the whipped topping into the pudding mixture until smooth and combined.

Once the cookies are completely cooled, spread a generous amount of the chocolate pudding frosting on top of each cookie.

Sprinkle crushed Oreo cookies over the frosting and top with gummy worms for decoration.