The bar had neither, but it got me asking why. “It’s for something I call the Sin of All Sins,” Carmellini explained: pours of Macallan 12 and a frosty Guinness—into separate glasses—that you down at the same time. Carmellini describes the drink—creamy, toasty stout on top of creamy, toasty Scotch—as both a perfect fall sipper and “something you should never ever do.” Is it a waste of good Scotch? Maybe, but the heart wants what the heart wants. So go ahead, join the sinful and try one for yourself.