Step 1:
Preheat the oven to 350°F. Prepare the yellow cake mix according to the package instructions. Bake in a well-greased 9×13 baking dish for the length of time listed on the box.
Step 2:
Let the cake cool completely.
Step 3:
In a mixing bowl, combine the pudding mix and milk. Whisk well until smooth. Let it sit for 5 minutes to thicken.
Step 4:
Using the handle of a large cooking spoon, poke holes all over the surface of the cake.
Step 5:
Pour the pudding over the cake, making sure it fills the holes. Chill the cake in the fridge for several hours.
Step 6:
Microwave the chocolate frosting in 15-second intervals until softened and pourable.
Step 7:
Pour the frosting over the cake and spread it into a smooth layer. Serve immediately or chill again before serving if desired.