Preheat your oven to 350°F (175°C). Grease an 8x8-inch baking pan or line it with parchment paper for easier removal.

In a mixing bowl, combine the melted butter and sugar, mixing until smooth. Add in eggs one at a time, mixing well after each addition, then stir in the vanilla extract.

In a separate bowl, whisk together the flour, baking powder, and salt.

Gradually add the dry ingredients to the wet mixture, stirring until just combined.

Gently fold in the fresh blueberries into the batter.

Pour the batter into the prepared baking pan and spread it out evenly. Bake for 30-35 minutes or until a toothpick inserted into the center comes out clean.

Allow the brownies to cool in the pan for about 10 minutes before transferring them to a wire rack to cool completely. Once cool, cut into squares and enjoy!