In the SUPERNATURAL episode "All Hell Breaks Loose, Part Two" (S02, Ep22), Sam and Dean's breakfast is made up of a bucket of fried chicken, a box of pizza, containers of Chinese food, 4 liters of cola, and a bottle of whiskey. Various flashbacks throughout the series show that this is a natural consequence of the two brothers growing up on the road without a mother and with a neglectful father who would leave them alone in motel rooms for weeks at a time. They learned to survive on meals of fast food slash junk food.
Calvin and Hobbes has Chocolate-Frosted Sugar Bombs, which Calvin sometimes makes even more disgustingly unhealthy by adding soda instead of milk or scooping spoonfuls of sugar into the cereal. They're crunchy on the outside, chewy on the inside, and they don't have a single natural ingredient or essential vitamin to get in the way of that rich fudgy taste.
Bill Cosby has a famous routine "Chocolate Cake for Breakfast" based on a real incident in which his wife demanded that he cook breakfast for their children. Not knowing what to serve the kids, he gives his youngest daughter the first thing she asks for—chocolate cake. Cosby rationalizes this by pointing out that cakes are made of eggs, flour, and milk, which are all nutritious. This goes on until his wife discovers what he'd done and sends him to his room... which is where he wanted to be in the first place.