Step 1: Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.
Step 2: In a large mixing bowl, combine the softened unsalted butter, granulated sugar, and brown sugar. Beat on medium speed until light and fluffy, about 2-3 minutes.
Step 3: Add the lemon zest, egg, and lemon extract. Beat until well combined.
Step 4: In a separate bowl, whisk together the all-purpose flour, baking soda, and salt. Gradually add to the wet mixture, mixing on low speed until just combined.
Step 5: Portion out the dough onto the prepared baking sheet, leaving space between cookies. Roll each portion in extra granulated sugar to coat.
Step 6: Bake for 10-12 minutes, or until the edges are lightly golden.
Step 7: While baking, prepare the glaze by whisking powdered sugar, lemon juice, and milk until drizzle-able.
Step 8: Allow cookies to cool for 5 minutes before transferring to a cooling rack. Drizzle the glaze over cooled cookies.
