Preheat your oven to 375° and line a muffin tin with 12 paper liners.
In a large bowl beat the softened butter until smooth. Add in the cup of sugar and blend until pale yellow.
Add eggs, one at a time and mix well after each egg is added.
Next measure and add in the vanilla, baking powder and salt. Mix just until combined.
Add in 1 cup of the flour and mix before pouring in 1/4 cup of milk, blending until combined.
Add remaining flour, mix and repeat with the remainder of the milk. Mix on medium speed until the batter is thick and smooth. Do not over mix.
Toss the blueberries in with a tablespoon of flour and stir to coat. Add the blueberries to the batter and use a rubber spatula to gently fold the blueberries into the batter.
Divide the muffin batter among muffin wells. Sprinkle with a little bit of turbinado sugar and then bake in a preheated oven for 15-18 minutes, rotating the pan halfway.
Repeat with the remaining batter
Let cool slightly before serving.