This is on the seventh level. It's semi-story related, so you'll get to it (sort of) without trying. Spoilers!
*** Spoiler - click to reveal ***About halfway through the level, the seagull from the start of the level eats the fish after its bowl breaks. The seagull then flies back to its perch at the start. Before you put the sticker of the fish cakes in its head, read the mind of the fish in its stomach.
Trophy!