Preheat the oven to 350°F (175°C).

In a large mixing bowl, whisk together the flour, sugar, cocoa powder, baking powder, baking soda, and salt.

Add the softened butter, eggs, vanilla extract, and milk to the dry ingredients and beat until just combined.

Pour the batter into a greased 9x13 inch baking pan and bake for 30 minutes or until a toothpick inserted into the center comes out clean.

Allow the cake to cool in the pan for 15 minutes, then use a toothpick or skewer to poke holes all over the cake.

In a bowl, stir together the sweetened condensed milk and half of the shredded coconut to make the coconut cream mixture.

Slowly pour the coconut cream mixture over the warm cake, allowing it to soak into the holes.

Spread the whipped topping evenly over the cake, sprinkle with the remaining shredded coconut, then chill in the refrigerator for at least 2 hours or overnight before serving.