Step 1

Prepare the cake for a 13x9 pan according to the package instructions. After baking, let cool on a wire rack for 15 minutes, then pierce with a fork all over the cake.

Step 2

Meanwhile, in a large bowl, whisk together the sweetened condensed milk, evaporated milk, milk and cocoa powder until well combined.

Step 3

Slowly pour over cake, taking care to fill all the holes created by the fork. If the cake stops absorbing the milk, let it soak in for a few minutes then continue pouring.

Step 4

In a clean, large bowl beat the whipping cream and sugar until medium peaks form. Spread over top of cake, cover and refrigerate for at least 1 hour or longer before serving.

Step 5

Garnish with chocolate shavings, if desired.