1-Gather and measure all ingredients precisely; preheat your oven to 350°F (175°C). Ensure any dietary substitutions are ready if needed.

2-In a medium bowl, whisk together 2 and 1/2 cups all-purpose flour, 1 teaspoon cornstarch, 1 teaspoon baking soda, and 1/2 teaspoon salt. Set aside.

3-In a large bowl, beat 3/4 cup unsalted butter, softened, and 1 cup plus 2 tablespoons granulated sugar on medium-high speed until creamy, about 3 minutes. Add 1 large egg at room temperature, 1/4 cup fresh or bottled lemon juice at room temperature, 1 tablespoon lemon zest (packed), and 1 teaspoon vanilla extract; beat on high speed until combined, about 1 minute. The batter may look curdled, which is normal. Scrape down the sides of the bowl.

4-Add the flour mixture to the wet ingredients and beat on low speed until combined. The dough will be thick, creamy, and sticky.

5-Cover the dough tightly and chill in the refrigerator for at least 3 hours or up to 3 days. Chilling is necessary for easy handling and to prevent spreading during baking.

6-Preheat the oven to 350°F if not already done. Line baking sheets with parchment paper or silicone baking mats.

7-Scoop the dough into 1-tablespoon portions (about 20 grams each) and roll into balls. Roll the dough balls first in 3 tablespoons granulated sugar (if using), then generously coat in 1 cup confectioners’ sugar (roll 2-3 times for a heavier coating). Place the dough balls on the baking sheets, spaced 3 inches apart.

8-Bake for 12 to 13 minutes, or until the edges appear set and the centers still look soft. If the cookies have not spread by the 9-minute mark, remove the baking sheet and gently tap it on the counter 2-3 times, then return it to the oven.

9-Allow the cookies to cool on the baking sheet for 5 minutes before transferring to a wire rack to cool completely. The cookies will slightly deflate as they cool. This recipe yields about 40 cookies.