Easy tres leches cake

1 yellow cake mix prepared and 

  baked (exchange the water for 

  milk and the oil for butter)

1 can sweetened condensed milk

1 can evaporated milk

1/2 cup whole milk or heavy cream

1 carton whipped topping

While cake is still warm, mix sweetened condensed milk, evaporated milk and milk or heavy cream together in a bowl. Poke holes in cake (I use a meat fork). Pour mixture over cake making sure to get it in all the holes. Place cake in the refrigerator to cool for at least 2 hours. Cover cake with whipped topping.