Step 1:
Preheat your oven according to the instructions on the white cake mix package, usually 350°F (175°C). Grease a 9×13-inch baking dish well to prevent sticking.

Step 2:
Prepare the white cake batter according to the package directions using the required eggs, oil, and water. Pour the batter into the prepared baking dish and bake as directed until a toothpick inserted in the center comes out clean.

Step 3:
Remove the cake from the oven and allow it to cool for about 10 minutes. While still warm, use the handle of a wooden spoon to poke holes all over the cake, spacing them evenly across the surface.

Step 4:
In a medium bowl, whisk together the cream of coconut and sweetened condensed milk until smooth and fully combined. Slowly pour this mixture evenly over the warm cake, allowing it to seep into the holes.

Step 5:
Let the cake cool completely, then spread the whipped topping evenly over the top. Sprinkle generously with flaked coconut and optional toasted coconut. Refrigerate for at least 4 hours before serving for the best flavor and texture.