Bake the Cake:
Preheat your oven to 350°F (175°C) and grease a 9x13-inch baking dish.
Prepare the chocolate cake batter according to the instructions on the box, adding vanilla extract if desired.
Pour the batter into the prepared baking dish and bake as directed on the box.
Once baked, remove the cake from the oven and allow it to cool slightly (about 10 minutes).
Prepare the Coconut Filling:
In a mixing bowl, combine the sweetened condensed milk, coconut milk, and coconut extract. Stir until smooth.
Poke and Soak:
Using a skewer or fork, poke holes all over the surface of the warm cake, ensuring the holes go deep enough to absorb the filling.
Slowly pour the coconut filling over the cake, allowing it to seep into the holes.
Let the cake cool completely to room temperature, then refrigerate for at least 2 hours to allow the flavors to meld.
Add the Topping:
Once the cake is chilled, spread the whipped topping evenly over the surface.
Sprinkle the shredded coconut on top (toast it beforehand for extra flavor, if desired).
Garnish with chocolate shavings or mini chocolate chips for an added touch of decadence.
Serve and Enjoy:
Slice and serve the cake chilled for the best flavor and texture.