For the cookies:
4 cups (16 oz.) cake flour
½ tsp. baking powder
½ tsp. salt
16 tbsp. (2 sticks) unsalted butter, softened but still cool
1¾ cups (12¼ oz.) sugar
2 large eggs, at room temperature
½ tsp. vanilla extract
¼ tsp. lemon extract
1 cup milk
For the glaze:
2 oz. unsweetened chocolate, chopped fine
¼ cup light corn syrup
1/3 cup water
5 cups (20 oz.) confectioners’ sugar
½ tsp. vanilla extract
Milk, as needed
step 1: Show Images
To make the cookies, preheat the oven to 375˚ F. Line 2 large baking sheets with parchment paper. In a large bowl combine the flour, baking powder and salt. Whisk to combine, and set aside.
step 2: Show Images
In the bowl of an electric mixer, beat the butter on medium speed until smooth and creamy, about 30 seconds. Add in the sugar gradually, increasing the speed to medium-high and beating until light and fluffy, about 3 minutes. Scrape down the sides of the bowl. Blend in the eggs, vanilla and lemon extracts at medium speed until combined, about 30 seconds. With the mixer on low speed, beginning and ending with the flour mixture, alternately add the flour mixture in four additions and the milk in 3 additions just until combined.
step 3: Show Images
Using a ¼-cup measuring cup and a spoon, place six ¼-cup mounds of dough a generous 2 inches apart on each baking sheet. (The “dough” will seem more like cake batter, and you will probably think you went wrong somewhere. Don’t worry, it’s supposed to be thin.) With moistened fingers, gently press each mound of dough into a disk 2½ inches wide and ¾ inch thick. Bake until the centers of the cookies are firm and the edges are just beginning to brown, about 20 minutes, rotating the baking pans halfway through the baking time. Cool the cookies on the baking sheets for 2 minutes. Use a wide spatula to transfer the cookies to a wire rack. Repeat with the remaining dough. Let cookies cool completely before icing.
step 4: Show Images
To make the icing, melt the chocolate in a medium bowl set over a saucepan of simmering water. Remove from the heat and set aside. In a medium saucepan, combine the corn syrup and water and bring to a boil. Remove from the heat and whisk in the confectioners’ sugar and vanilla until combined. Transfer ¾ cup of the vanilla icing to the bowl with the melted chocolate and stir to combine. (I found that the chocolate glaze was far too thick so I whisked in 1 teaspoon of milk at a time until it had a consistency similar to that of the vanilla glaze.)
step 5: Show Images
To glaze the cookies, place the cookies on wire racks set over waxed paper or foil. Use a small offset spatula to spread about 2 tablespoons of the vanilla icing on half the flat side (bottom) of each cookie. Tilt the cookie and run the spatula around the edge to scrape off excess icing. Allow to harden slightly, about 15 minutes. If the icing begins to thicken, stir in milk 1 teaspoon at a time as needed. Using the offset spatula, spread the chocolate icing over the other half of each cookie, scraping away excess icing from the edge. Allow the glaze to set at least 1 hour before serving. The cookies can be stored in an airtight container layered between sheets of parchment paper for up to 3 days.