Only on the "CBS This Morning" podcast, best-selling author Clay Risen discusses everything you need to know about Scottish single malt whiskey with "CBS Evening News" anchor Jeff Glor. After the success of his first book, a guide on American whiskey, Risen has turned his focus across the Atlantic with "Single Malt: A Guide to the Whiskies of Scotland." He shares details on the tasting process, which single malts are worth trying and which distilleries to visit when traveling to Scotland.