I saw a macaronic film last night, which of course relates directly to macaroni cheese, Yankee Doodle's befeathered hat, and a penguin.
The film was La Grande Illusion, which is about French prisoners in Germany in WWI. It therefore shifts between French and German, and, interestingly, when aristocrats wish to talk to each other without the rabble understanding what they're saying, they shift into English. This mixing of languages is called macaronic, because the languages are beaten together in the same way that flour and other ingredients are beaten together to make the great Italian dish macaroni.
So great was the Italian dish of macaroni, that rich C18th travellers would come back to England raving about how delicious macaroni was. They even founded a club called the Macaroni Club at which they could meet, eat macaroni, and discuss how rich and stylish and well-travelled and too-good-for-England they were.
Or maybe they didn't. Though Horatio Walpole did mention in a letter of 1764:
The Maccaroni Club (which is composed of all the travelled young men who wear long curls and spying-glasses).
It's quite possible that he was making the club up, in the way I could dismissively say that people were all members of The Coke and Cocktails Club as a sort of joke.
Anyway, the term caught on and soon any young fop who tried to affect foreign fashions was called a macaroni, which is why when the foolish Yankee Doodle puts a feather in his cap, he called it macaroni.
And finally, there's the question of what you call a foppish penguin. You see, there's a species of penguin that looks as though it spends all its time dying and styling its hair into the most ridiculous fashions, just like a macaronic fop. The species is therefore called the Macaroni Penguin.