Can Be Chocolate, or a Fungus Found Underground
Puzzle 7 of Buying Books Piece of Cake Pack
Question is: Can Be Chocolate, or a Fungus Found Underground
and the answer is: TRUFFLE
Word Meaning:
TRUFFLE — Any of various edible fungi, of the genus Tuber, that grow in the soil in southern Europe; the earthnut.
Definitions from Wiktionary.