Preheat your oven to 350°F (175°C).
In a mixing bowl, cream together the softened butter and sugar.
Add the egg and vanilla extract, mixing until well combined.
In another bowl, whisk together flour, baking powder, and salt.
Gradually add the dry ingredients to the wet mixture, stirring until just combined.
Gently fold in the fresh blueberries.
Drop rounded tablespoons of dough onto a baking sheet lined with parchment paper.
Bake for 12-15 minutes or until edges are lightly golden.
Remove from the oven and let cool on a wire rack.
Dust with powdered sugar before serving.