Pre-heat your oven to 375 degrees. Line a standard 12-cup muffin tin with liners or coat with non-stick cooking spray. Set aside.
In a medium bowl, mix the butter, eggs, milk together.
In a large bowl, whisk flour, 3/4 cup sugar, baking powder and salt.
Stir wet ingredients into dry ingredients then gently fold in the blueberries using a spatula or wooden spoon.
Scoop the muffin batter into your prepared muffin tin, dividing the batter evenly between the 12 cups. Sprinkle the tops of the muffins with the remaining tablespoon of sugar.
Transfer to your pre-heated oven and bake for 25-28 minutes, or until a toothpick inserted into the center comes out clean. Allow the muffins to cool in their tin for 5-10 minutes. Then remove and transfer them to a wire rack to continue cooling.
These blueberry muffins can be stored at room temperature in an airtight container for 2-3 days.