In a large mixing bowl, cream together the softened butter and granulated sugar until light and fluffy. Add the eggs one at a time, beating well after each addition. Stir in the vanilla extract, lemon zest, and lemon juice.

In a separate bowl, whisk together the flour, baking powder, and salt. Gradually add the dry ingredients to the wet mixture, mixing until just combined.

Gently fold in the fresh blueberries, being careful not to crush them. This will ensure pockets of juicy berries in each cookie.

Cover the dough with plastic wrap and chill in the refrigerator for at least 30 minutes to make it easier to handle and prevent spreading during baking.

Preheat your oven to 350°F (175°C). Line a baking sheet with parchment paper. Using a cookie scoop, drop dough onto the prepared sheet, leaving space between each cookie. Bake for 12-15 minutes, or until the edges are lightly golden.

Allow cookies to cool on the baking sheet for 5 minutes before transferring to a wire rack to cool completely. Serve them fresh with a cup of tea or coffee.

Store leftover cookies in an airtight container at room temperature for up to a week. For longer storage, freeze in a zip-top bag for up to three months.