Here's the picture from a while ago:
And here's the recipe, taken from A Best Recipe Classic: Baking Illustrated, put together by the editors of Cook's Illustrated Magazine. Keep in mind that I had to alter for elevation (mind you, this typed out version has not been altered, but just in case yours come out tasting like shit... well, perhaps you need to find a kitchen at 7, 200 feet):
- 2 cups unbleached all-purpose flour
- 1 tablespoon baking powder
- 1/2 teaspoon salt
- 1 large egg
- 1 cup sugar
- 4 tablespoons unsalted butter, melted and cooled slightly
- 1 1/4 cups sour cream
- 1 1/2 cups fresh blueberries
Whisk the flour, baking powder, and salt in a medium bowl until combined. Whisk the egg in a second medium bowl until well-combined and light-colored, about 20 seconds. Add the sugar and whisk vigorously until thick and homogenous, about 30 seconds; add the melted butter in 2 or 3 additions, whisking to combine after each addition. Add the sour cream in 2 additions, whisking just to combine.
Add the berries to the dry ingredients and gently toss just to combine. Add the sour cream mixture and fold with a rubber spatula until the batter comes together and the berries are evenly distributed, about 25 to 30 seconds. (Small spots of flour may remain and the batter will be thick. Now, in the voice of Faye Dunaway as she channeled Joan Crawford during the wire hanger scene, scream this at yourself lest you forget: "Do not overmix! Do not overmix! Do not overmix!")
Using a large spoon sprayed with nonstick cooking spray to prevent sticking, divide the batter among the greased muffin cups. Bake until the muffins are light golden brown and a toothpick comes out clean, 25 to 30 minutes, rotating the pan from front to back halfway through the baking time. Invert the muffins onto a wire rack, stand the muffins upright, and cool 5 minutes. Serve as is (or with a couple of dollops of butter smeared on top).