For the cookies:

• 2 ½ cups all-purpose flour
• 1 ½ tsp baking powder
• ¼ tsp salt
• ¾ cup unsalted butter, softened to room temperature
• ¾ cup granulated sugar
• ¼ cup light brown sugar
• 1 large egg
• 1 ½ tsp pure vanilla extract
• 2 tsp lemon zest
• 2 tbsps lemon juice
• ¼ cup milk
• 2 cups fresh blueberries 

For the glaze:    

• 1 cups confectioners’ sugar, sifted
• 2 tbsp lemon juice
• 1 tbsp heavy cream