Hidden by Leprechauns at the End of a Rainbow
Puzzle 13 of Justin Timberlake Piece of Cake Pack
Question is: Hidden by Leprechauns at the End of a Rainbow
and the answer is: POTOFGOLD
Word Meaning:
POT — A flat-bottomed vessel (usually metal) used for cooking food, possibly excluding saucepans (see usage notes).
Definitions from Wiktionary.