Hazelnut syrup is a warm, toasted infusion made by simmering roasted hazelnut pieces or natural nut extracts with sugar and water until it develops a rich, golden clarity. Thanks to the earthy oils and buttery characteristics of the nut, it delivers smooth, nutty, and praline-like notes—often deepened with a hint of caramelized sugar or a touch of salt—making coffee lattes, hot chocolates, and dessert cocktails taste creamier, more indulgent, and more "roastery-fresh" than regular simple syrup.