Preheat your oven to 350°F (175°C). Line a baking sheet with parchment paper or a silicone baking mat.

In a medium bowl, whisk together the flour, baking powder, baking soda, and salt. Set aside.
In a large mixing bowl, beat the butter and sugar together until light and fluffy (about 5-8 minutes). Add the egg, lemon zest, and vanilla extract, beat until fully incorporated.
Gradually add the dry ingredients into the wet mixture, mixing until just combined.

Gently fold in the blueberries using a spatula, being careful not to crush them.

Scoop out dough (about 1 ½ tablespoons per cookie) and roll into balls.

Roll each dough ball in the extra granulated sugar for a crisp, sugary coating.

Place cookies 2 inches apart on the prepared baking sheet. Press down gently. (You can refrigerate for 30 minutes or longer if desired.)

Bake for 10-12 minutes, or until the edges are lightly golden and the centers are just set.

Let cookies cool on the baking sheet for 5 minutes, then transfer to a wire rack to cool completely.