Have the Cake Challenge: black and white cookies

Black and white cookies have always interested me.  Never having tasted one, I was just intrigued by the name, so when this month's Have the Cake challenge was to make either Black & White Cookies or Linzer cookies... well, of course I had to make the Black & White!  From what I understand, these cookies are quite popular in the North Eastern states, particularly New York. They are more cake like in texture rather than the crispy or chewy texture one would expect from a cookie.  I did a combination of two recipes, the dough from Smitten Kitten and the glaze  from Joy of Baking

Black and White Cookies
 Smitten Kitten's recipe which she adapted from a bunch of places, but mostly Zabar’s

1 3/4 cups granulated sugar
1 cup unsalted butter (2 sticks), at room temperature
4 large eggs
1 1/2 cups milk
1/2 teaspoon vanilla extract
1/4 teaspoon lemon extract
2 1/2 cups cake flour
2 1/2 cups all-purpose flour
1/2 teaspoon baking powder
1/2 teaspoon salt

Glaze:

from Joy the Baker

4 cups confectioners sugar
1/3 - 1/2 cup hot water
2 tablespoons light corn syrup
1/2 teaspoon pure vanilla extract
1 ounce (30 grams) bittersweet or semi-sweet chocolate, finely chopped 

Directions: 

 Preheat oven to 375 degrees. Spray 2 baking sheets with nonstick spray, or use a Silpat (silicone baking sheet).  I don't like to use parchment paper on sticky cookies but that is an option, too.

In large mixing bowl, combine sugar and butter; mix until fluffy.  Generally this takes 3-5 minutes, it will depend on room temperature, temperature of the butter. You can tell when they are “light and fluffy” by the appearance; it should be very light in color. Next, add the eggs, milk and vanilla and lemon extracts; mix until smooth.

In medium bowl, combine cake flour, all-purpose flour, baking powder and salt; gently whisk together.  Add dry mixture to the wet in batches, stirring well after each addition. 

Place heaping spoonfuls of the dough 2 inches apart on the baking sheets;bake until edges begin to brown, 18 to 20 minutes. Let cookies cool completely.

Glaze:
Place the confectioners sugar in a large bowl. Gradually Stir in the hot water (it is best to pour in a bit at a time so that you can keep track of its consistency easier), add corn syrup,and vanilla extract, stirring constantly, until the mixture is thick, smooth, and of spreading consistency. Add more sugar or water if necessary to get the right consistency.

Remove about 1/2 cup (120 ml) of the frosting and place it in another bowl. In a small microwavable bowl, add the finely chopped chocolate. Melt on high for about thirty seconds; stir. Add the melted chocolate to the 1/2 cup frosting.

Turn the cookies so the flat bottoms are facing up. Spread white glaze over half the cookie. Repeat with the remaining cookies. If the frosting/glaze thickens too much, add a few drops of water.

Once all the cookies are covered with the white frosting, then cover the other half of each cookie with the chocolate frosting. If the chocolate frosting becomes too thick, add a little hot water to thin the frosting.