The first step is to bake the cake according to the package's directions using a 9×13-in. baking pan.

Poke holes in the hot cake.

Mix together your 2 cups of milk and 1 package of the Hershey's instant chocolate pudding mix and pour this mixture over the cake, filling the holes. The quicker you do this process the better as the pudding starts to set up quickly and it makes it much harder to put down the holes.

Microwave the hot fudge topping (with the lid off) for about 30 - 45 seconds or until it pours easily.

Pour the fudge evenly over the top of the cake and let the cake cool completely.

In a medium bowl, combine the second pudding mix with the additional 2 cups of milk, once combined carefully fold in the Cool Whip.

Spread the mixture evenly over the top of the cake.

Sprinkle the chocolate chips (or chocolate shavings) over the top and refrigerate for at least 4 hours before serving. The longer it sits the better as the pudding gets set up really well and allows it time to get nice and cold.

Store this cake covered in the fridge for up to 3 days.