The phrase 'Piece of Cake' is used to describe something that is very easy to complete.
Example of Use: "The boy found the project to be a piece of cake because it was incredibly easy."
Interesting fact about Piece of Cake
The idea of cake, which is literally a flat, sweet baked item, as being easy, originated sometime during the 1870s, when cakes where often handed out as prizes in cakewalks, which were easy competitions to win. As for the origin of the idiom 'a piece of cake,' Ogden Nash was the first to use it in print when he wrote “Her picture’s in the papers now, and life’s a piece of cake” in his 1936 work Primrose Path.
