01 -
Preheat your oven to 350°F (175°C). Lightly grease a 9x13-inch baking dish with cooking spray or butter, or line it with parchment paper for easier removal. If using parchment, leave some overhang on the sides to create handles.
02 -
In a large mixing bowl, combine the chocolate cake mix, 3 eggs, 1/2 cup vegetable oil, and 1 cup water. Mix according to the package instructions, typically about 2 minutes with an electric mixer on medium speed, until the batter is smooth and well combined. Make sure to scrape down the sides of the bowl to incorporate all the dry ingredients.
03 -
Pour the cake batter into your prepared baking dish, spreading it evenly with a spatula. Bake in the preheated oven for 25-30 minutes, or until a toothpick inserted into the center comes out clean or with just a few moist crumbs. Don't overbake, as this can make the cake dry.
04 -
While the cake is baking, make the coconut filling. In a medium bowl, combine the sweetened condensed milk, shredded coconut, and powdered sugar. Stir until thoroughly mixed. The mixture will be thick and sticky - this is perfect as it will create a luscious middle layer in your cake.
05 -
When the cake is done baking, remove it from the oven and place it on a cooling rack. Allow it to cool for about 10 minutes, but add the coconut filling while the cake is still warm. This helps the filling to slightly melt into the top of the cake. Carefully spread the coconut mixture evenly over the warm cake, going all the way to the edges.
06 -
For the chocolate ganache, pour the heavy cream into a medium saucepan and heat over medium heat. Watch it carefully and remove from heat just as it begins to simmer - you'll see small bubbles forming around the edges. Do not let it come to a full boil. Immediately pour the hot cream over the chocolate chips in a heatproof bowl. Let it sit undisturbed for 1-2 minutes to allow the chocolate to begin melting, then stir gently with a whisk until smooth and glossy. Stir in the vanilla extract at the end for flavor.
07 -
While the ganache is still warm and pourable, slowly pour it over the coconut layer, covering it completely. Use an offset spatula or the back of a spoon to spread it evenly, working quickly before the ganache starts to set. If desired, sprinkle additional coconut or chocolate shavings on top for decoration.
08 -
Refrigerate the cake for at least 1 hour, or until the chocolate layer is completely set. This chilling time allows all the layers to meld together beautifully and makes the cake easier to slice cleanly. Cut into squares and serve chilled or at room temperature. Store any leftovers covered in the refrigerator for up to 5 days.