Makes 12 muffins (Cooks Illustrated)
2 cups (10 ounces) unbleached all-purpose flour
1 cup (4 1/2 ounces) fine-ground, whole grain yellow cornmeal
1 1/2 teaspoons baking powder
1 teaspoon baking soda
1/2 teaspoon salt
2 large eggs
3/4 cup (5 1/4 ounces) sugar (I did 1/2 cup)
8 tablespoons (1 stick) unsalted butter, melted
3/4 cup sour cream
1/2 cup milk
Adjust an oven rack to the middle position and heat the oven to 400 degrees. Spray a standard muffin tin with non-stick cooking spray.
Whisk the flour, cornmeal, baking powder, baking soda, and salt in a medium bowl to combine; set aside. Whisk the eggs in a second medium bowl until well-combined and light-colored, about 20 seconds. Add the sugar to the eggs, whisk vigorously until thick and homogenous, about 30 seconds; add the melted butter in 3 additions, whisking to combine after each addition. Add half the sour cream and half the milk and whisk to combine; whisk in the remaining sour cream and milk until combined.
Add the wet ingredients to the dry ingredients; mix gently with a rubber spatula until the batter is just combined and evenly moistened. Do not over-mix. Using an ice cream scoop or large spoon, divide the batter evenly among muffin cups, dropping it to form mounds. Do not level or flatten the surface of the mounds.
Bake until the muffins are light golden brown and a skewer inserted into the center comes out clean, about 18 minutes, rotating the muffin tin from front to back halfway through the baking time. Cool the muffins in the tin for 5 minutes; invert the muffins onto a wire rack, stand the muffins upright, cool 5 minutes longer, and serve warm.