Which mushroom is considered a delicate delicacy and very expensive?

Black Truffle

The black truffle, an underground mushroom prized in haute cuisine, is famous for its rich and complex taste as well as its distinctive aroma. The harvesting of truffles, often with the help of trained dogs or pigs, is an ancient culinary tradition, especially in France and Italy. Their rarity and the difficulty of harvesting explain the high price of truffles on the international market, where they can sell for thousands of dollars per kilogram.