Bourbon has one of the most famous recipes in the world: It must be made with at least 51 percent corn in its mash. Beyond this, bourbon distillers often use rye and malted barley to finish the grist. William Larue Weller did things a little differently. Where many other bourbons use rye, W.L. Weller uses wheat. Weller himself developed this recipe, believing wheat produced a softer, sweeter flavor profile than rye’s typically spicy one.