Tonka bean smells like a deep, warm mix of vanilla, sweet almond, and a touch of spice. It’s comforting, but also complex and a little mysterious. It’s often used as a base note to give a fragrance some heft and staying power. Tonka bean often smells like the rich scent of a fancy dessert (that isn't just plain vanilla). It mixes really well with other notes, adding a smooth, slightly nutty sweetness.