2 cups cake flour
2 cups all-purpose flour
1/2 teaspoon baking powder
1/2 teaspoon kosher salt
1 cup unsalted butter, at room temperature
1 3/4 cups sugar
1/2 teaspoon vanilla extract or vanilla paste
1/2 teaspoon lemon extract
1 cup whole milk
3 ounces bittersweet or unsweetened chocolate, chopped
1/2 cup water
3 tablespoons corn syrup
5 cups powdered sugar
1/2 teaspoon vanilla paste
To make the cookies: Preheat oven to 375 degrees. Line baking sheet(s) with parchment paper.In a medium bowl, whisk together the flours, baking powder, and salt; set aside.
In the bowl of a stand mixer or a large bowl (using hand mixer), beat the butter until creamy. Add in the sugar until well combined and the mixture is light and fluffy. Add the eggs and mix till they are incorporated. In a medium sized bowl combine the flours, baking powder, and salt. Add 1/3 of the flour mixture to the butter mixture and blend until just combined. Add in half of the milk, mixing until just combined. Repeat with the remaining flour and milk, ending with the final 1/3 of the flour mixture. Stir in the lemon extract and vanilla extract until combined, being careful not to over mix. This will be a loose batter. Not think like cookie batter.
Drop the batter by either using a large ice cream scoop or use 1/4 cup measuring cup onto the prepared baking sheet(s), leaving 2 inches between the cookies. Bake until centers are firm and edges just begin to brown, 15-18 minutes. Cool the cookies for 2 minutes on the sheet before transferring to a wire cooling rack. Allow to cool completely before icing. Once the cookies are completely cooled, flip them over.
To make the icing:
Melt the chocolate in a small bowl in a microwave. Set aside.
In a small saucepan set over medium high heat, bring the water and corn syrup to a boil. Remove from heat and add half of the mixture into the sugar. Whisk until fully incorporated and smooth, adding more of the corn syrup mixture, 1 teaspoon at a time, as needed. Stir in the vanilla extract. You want the icing to be "spoonable" yet not too thick.
Fill a Ziploc bag with a small amount of white icing and snip off the end. Draw a straight line directly across the center of the bottom of each cookie. That will help you keep the frosting on their respective sides... Using a small offset spatula, spread vanilla icing over half of each cookie, filling it in up to the line.
Once all of the cookie have vanilla icing, stir the melted chocolate into the remaining vanilla icing. If needed, stir in any remaining corn syrup mixture, 1 teaspoon at a time, as needed.
Now, do the same for the chocolate! Allow the cookie icing to setup on a wire cooling rack.