Preheat oven to 350℉
Line muffin tin with cupcake liners or lightly grease with butter.
In a medium bowl, stir together flour, baking powder, and salt.
In a stand mixer with the paddle attachment, cream the butter and sugar on medium speed until light and fluffy (see note on texture). Reduce the speed to low and slowly add the eggs and vanilla. Turn the mixer to medium speed and mix until well incorporated
On low speed, add half of the flour mixture, half of the sour cream, and then the remaining flour mixture and sour cream. Mix until well incorporated and gently fold in blueberries.
Using a ¼ cup measure, fill the prepared muffin cups ¾ full.
Bake until a toothpick inserted into the center of a muffin comes out clean (about 25-30 minutes).
Allow to cool at least 15 minutes before serving.