1 3/4 cups flour
1/2 tsp baking powder
1/2 tsp baking soda
1/2 cup sour cream (room temp)
1/2 cup buttermilk (room temp)
1/2 tsp vanilla
1/2 tsp kosher salt
1/2 cup butter, softened
3/4 cup sugar
2 eggs (room temp)
1 1/4 cup blueberries
Raw sugar for sprinkling
Preheat oven to 375 degrees. In a bowl, sift together the flour, baking powder, and soda. Reserve 1/4 cup of dry ingredients for coating the blueberries later.
In another bowl, mix together the sour cream, buttermilk, vanilla, and salt. Set the wet ingredients aside.
In a mixer, combine the butter and sugar and mix on med-high speed with the paddle attachment until pale and well whipped, about 3 minutes. Turn the mixer down to medium and add the eggs one at a time, allowing each egg to be completely incorporated before the next addition. Add the dry ingredients and the wet ingredients to the batter in 3 additions, alternating wet and dry and ending with dry. Do not overmix.
Put the blueberries in a small bowl and toss them with the reserved 1/4 cup of dry ingredients to coat the berries. Fold into the batter.
Put in muffin tin, sprinkle with sugar and bake 23-25 minutes, rotating the pan halfway. Cool in tin 10 minutes before removing muffins.