Instructions

• Whisk the flour, cornstarch, baking soda, and salt together in a medium bowl. Set aside.
• In a large bowl, beat the butter and granulated sugar together on medium-high speed until creamed, about 3 minutes. Add the egg, lemon juice, lemon zest, and vanilla extract and beat on high speed until combined. Scrape down the sides and bottom of the bowl. Add the flour mixture and beat on low speed until combined.
• Cover dough tightly and chill in the refrigerator for at least 3 hours and up to 3 days.
• Remove cookie dough from the refrigerator and let it sit at room temperature for about 10 minutes if it chilled longer than 3 hours.
• Preheat oven to 350°F (177°C) and line baking sheets with parchment paper.
• Scoop and roll balls of dough, about 1 tablespoon each, into balls. Roll the balls in granulated sugar first and then generously in confectioners’ sugar. Place them 3 inches apart on baking sheets.
• Bake the cookies for 12–13 minutes or until edges appear set and centers look soft. If not spreading by minute 9, lightly bang the baking sheet on the counter and return to the oven.
• Cool cookies for 5 minutes on the baking sheet, then transfer to a cooling rack to cool completely.
• Cookies stay fresh covered at room temperature for up to 1 week.