Jack Daniel’s Single Barrel Heritage Barrel’s flavor is derived from a unique high toast, low char barrel toasting technique. This barrel is a modern interpretation of Jack Daniel’s earliest barrel-making process to create a deeper, richer toasted layer before being charred. Single Barrel Heritage Barrel has a soft oak nose infused with vanilla and graham cracker, rich notes of vanilla, marshmallow and toffee across the palate and a lingering finish of brown sugar.