Preheat your oven to 375°F (190°C) to ensure even baking.
Lightly grease your muffin top pan or line it with parchment paper.
In a large mixing bowl, cream together the softened unsalted butter and ¾ cup granulated sugar until light and fluffy.
Add the large egg and vanilla extract, mixing until fully combined.
In a separate bowl, whisk together 1 cup of all-purpose flour, salt, baking powder, and baking soda.
Gradually add the dry mixture to the creamed butter mixture, alternating with buttermilk, starting and ending with dry ingredients.
Gently fold in 1 cup of fresh blueberries coated with reserved flour.
Using a large cookie scoop, drop the batter into the prepared muffin top pan, filling each cavity about ¾ full. Optionally, sprinkle extra sugar on top.
Bake for 15-18 minutes until golden brown and a toothpick comes out clean.
Allow to cool for 5 minutes in the pan before transferring to a wire rack.
