Saying something is really easy

Ser pan comido

sehr pan koh-MEE-doh — To be a piece of cake (very easy)

"El examen fue pan comido."
The exam was a piece of cake.

Literally "to be bread already eaten" — same meaning as the English idiom, just built from a different food image.

"What I tell nervous students right before their first oral exam, whether or not it's entirely true."— Graciela