Preparation

• Make the lemon curd first. I like to make the curd the day before so it's chilled and ready to go when making these cookies.
• Whisk the dry ingredients together in a large mixing bowl: All-purpose flour, cake flour, cornstarch, baking powder, baking soda, and salt. Set aside.
• Using a stand mixer fitted with the paddle attachment, cream the butter and sugar on medium speed until combined, about 2-3 minutes. Scrape down the sides of the bowl as needed.
• Add in the egg, egg yolk, lemon juice, lemon zest, lemon extract, and vanilla extract. Gradually add in the dry ingredients just until combined, careful not to over mix.
• Chill the dough for at least 30 minutes, or up to 3 days.
• Preheat the oven to 350°F. Line two baking sheets with parchment paper or silicone baking mats.
• Let the dough sit at room temperature for a few minutes. Then scoop and roll the cookie dough into 1-1.5 tablespoon sized balls. Roll in granulated sugar first, then in powdered sugar, and place on the prepared cookie sheet.
• Use your thumb or a wine cork to press a shallow indentation into the middle of each cookie. Fill each indent with about 1 teaspoon chilled lemon curd.
• Bake for 9-10 minutes or until the edges are lightly golden brown. Remove from the oven and transfer to a cooling rack.
• If cookies aren't perfectly circular, use a circular cookie cutter or a glass around one of the cookies while still warm to smooth out uneven edges.
• Add more lemon curd if desired and dust with additional powdered sugar.
• Store lemon curd cookies in the refrigerator for up to 4 days.