The Best Glazed Mixed Berry Scones

"These are the best scones I've ever had, and they've changed my mind about scones in general, which are too often dry and bland. They're incredibly easy, you don't need to dirty a food processor or a mixer, and are a guaranteed-to-disappear weekend breakfast, brunch, or impromptu dessert or snack. They're flaky, tender, and supremely moist. Sour cream is used which not only moisturizes and tenderizes the dough, but since it's cultured, it helps the scones rise higher and stay fluffier and lighter, without being airy or dry. I used a frozen berry medley, but fresh can be used, noting that baking time will likely be reduced. It's a great blank canvas base recipe for scones, and most any fresh fruit, dried fruit, or zest can be added. Use what you have, enjoy, and is seasonal. For example, citrus zest can be added to the dough and citrus juice can by used in the glaze...."