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

2-In a large bowl: cream together 1 cup (226 g) softened unsalted butter, ¾ cup (150 g) granulated sugar, and 2 tablespoons fresh lemon zest using an electric mixer until light and fluffy.

3-In a separate bowl: whisk together 2 cups (250 g) all-purpose flour, 2 tablespoons cornstarch, and ½ teaspoon salt. Gradually add the dry ingredients to the wet ingredients and stir until combined.

4-Scoop the dough: into 1 tablespoon-sized balls, roll them gently between your palms to form smooth balls, and place them on the baking sheet at least 2 inches apart.

5-Bake: for 8-10 minutes on the center oven rack.

6-Immediately after baking: flatten each cookie gently with the bottom of a measuring cup or glass to create a flat surface and achieve a soft texture.

7-Allow the cookies: to cool completely.

8-For the icing: whisk 1 ¾ cups (220 g) powdered sugar and 2 tablespoons fresh-squeezed lemon juice together in a small bowl until smooth and slightly thickened. Adjust the consistency by adding more powdered sugar if too thin or more lemon juice if too thick.

9-Spread the lemon icing: over the cooled cookies and garnish with lemon zest if desired. Let the glaze set before serving.