Truffles.

Truffles are unknown to many, strange, and yummy.  They come in black and white varieties, and are found mostly in Europe, especially Italy.  They are delicious on pasta.  They are remarkably expensive, and small, but their out-of-this world taste makes it worth it.  The white truffles are in season from October to December, and the black ones are in season in late autumn and winter, reaching their peak in January.

Truffles are a type of fungus, like mushrooms, except they grow underground and are rarer and smaller.  It is for this that they are so much more expensive.  Truffles are best when fresh, and they can easily make a meal the best meal ever!