It's a trend 500 years in the making. Cask-aged vodka, or starka, has been popular in Eastern Europe since the 15th century, when families buried barrels of the stuff when a child was born and dug it up to drink on their wedding day. There's a reason they went to all that trouble: "The barrel mellows the vodka and makes it more complex," says Lee Medoff, founder of Bull Run Distillery and one of the creators of the Oregon Starka Project, a collaboration of three distilleries to create signature barrel-aged vodkas. "Meanwhile, the spirit pulls flavors out of the wood — vanilla, caramel, chocolate, and fruit."\r\nRELATED: Why Your Next Bottle of Gin Should Be Barrel-Aged\r\nAlthough bottles of flavored vodka have been taking up more space on shelves in recent years, they mostly came from artificial ingredients. Thanks to a growing interest in more natural, less processed food and drink, barrel-aged vodka is now becoming widely available in the States. Here are the bottles to get you started. The first five work beautifully in cocktails that call for whiskey, like a Manhattan or old-fashioned. But before you get out your shaker, we suggest you sip them straight, something only Russians dared to do with this once bland liquor.