Recipe originally posted by Christianne Winthrop on Serious Eats. Her description: "I'm fond of blueberry, especially recipes that include a crunchy cinnamon sugar topping. But after reading that the average coffee shop muffin weighs in at around 350 calories, I decided that there had to be another way to get that flavor. That's how the Blueberry Muffin Smoothie was born. This smoothie is creamy and full of blueberries, with just a pinch of cinnamon and a dash of vanilla, making it a little reminiscent of muffin batter. Where traditional blueberry muffins are chock full of white sugar, this blueberry smoothie scores extra points for being significantly healthier."