Heat oven to 400° F.
Grease & flour muffin tin.
In mixing bowl, whisk together flour, baking powder, sugar and salt.
Add cubed butter to flour mixture and beat with paddle attachment until butter is mostly incorporated. You should be able to see some pea-sized pieces of butter.
In small mixing bowl, whisk together the milk, vanilla extract.
With mixer on medium speed, slowly add milk mixture to flour mixture until mixture comes together and leaves the side of the bowl.
Increase mixer speed to medium high and add eggs one at a time, beating between first addition. Scrape down bowl and continue to beat for another minute until batter is smooth.
Stir in blueberries.
Fill muffin tin cups to 3/4 full.
Bake for 15 minutes or until golden brown and toothpick comes out dry when inserted in center of a muffin.