**Preheat Oven:** Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.

**Cream Butter and Sugar:** In a large bowl, beat the butter and sugar together until light and fluffy.

**Add Wet Ingredients:** Mix in the egg, lemon zest, and lemon juice until well combined.

**Mix Dry Ingredients:** In a separate bowl, whisk together the flour, baking powder, baking soda, and salt. Gradually add the dry ingredients to the wet mixture, stirring until just combined.

**Fold in Blueberries:** Gently fold in the blueberries, being careful not to crush them.

**Portion Dough:** Use a cookie scoop or spoon to drop tablespoon-sized portions of dough onto the prepared baking sheet, spacing them about 2 inches apart.

**Bake:** Bake for 10–12 minutes, or until the edges are lightly golden. Allow cookies to cool on the baking sheet for 5 minutes before transferring to a cooling rack.

**Prepare the Glaze:** In a small bowl, whisk together the powdered sugar and lemon juice until smooth. Adjust the consistency with more juice or sugar as needed.

**Glaze the Cookies:** Drizzle the glaze over the cooled cookies. Let the glaze set before serving.