Black and White Cookies

Just before Father's Day, I asked Twitter to recommend some chocolate cookies for me to make for a gift. I got some great suggestions (Love and Olive Oil's Double Chocolate Chipotle Cookies, these Brown Butter Pecan Praline Oatmeal Cookies with chocolate chips and a chocolate glaze), but after I looked through Pinterest and saw a picture of black and white cookies, I couldn't get my mind off of them. After looking through the first recipe that popped up in my Google search, I was struck by how easy they seemed to be to make, too. How could a cookie as good as this be so easy? And if it's so easy, why aren't more bakeries making good versions of them? (Really, the ones I've had outside NYC were meh, at best.)

These cookies are a favorite in the Eats household. Mr. Eats and I "babymooned" in New York City and ate lots of potatoes, bagels, and black and white cookies. But they're only shaped like cookies; they're actually small, round, flat cakes (vanilla, sometimes with a hint of lemon) frosted with vanilla-lemon glaze on one side and chocolate glaze on the other side. And they're usually huge. Like, four or five inches wide.

Anyhoo, this recipe comes from Epicurious/Gourmet, which I trust, but I still read through several pages of reviews to get some tips. One of the best tips was to double the recipe because you are definitely going to want plenty of these cookies (the only part I didn't double was the amount of cocoa for the chocolate frosting). I used a large cookie scoop that yielded cookies that were about three to three and a half inches wide and I got an even three dozen. Enough to snack on for a while and to put some in the freezer for a nice treat at a later date. But I left the measurements of the original recipe.

Black and White Cookies
adapted from Gourmet/epicurious.com
yield: about 18 3" cookies
Please see the notes section at bottom before making these cookies.

For the cookies:
1 1/4 cups all-purpose flour
1/2 teaspoon baking soda
1/2 teaspoon salt
1/3 cup well-shaken buttermilk
1/2 teaspoon vanilla
1/3 cup (5 1/3 tablespoons) unsalted butter, softened
1/2 cup granulated sugar
1 large egg, room temperature

For the frosting:
1 1/2 cups confectioners sugar
1 tablespoon light corn syrup
2 teaspoons fresh lemon juice
1/4 teaspoon vanilla
1 to 2 tablespoons milk
2 to 4 tablespoons unsweetened Dutch-process cocoa powder

Preheat oven to 350°F.

Whisk together flour, baking soda, and salt in a bowl. Stir together buttermilk and vanilla in a cup.

Beat together butter and sugar in a large bowl with an electric mixer until pale and fluffy, about 3 minutes, then add egg, beating until combined well. Mix in flour mixture and buttermilk mixture alternately in batches at low speed (scraping down side of bowl occasionally), beginning and ending with flour mixture. Mix until smooth.

Spoon two-tablespoon-size dollops of batter about 2 inches apart onto a buttered large baking sheet. Dip fingers in a bit of water and tamp scoops down into a disk shape about 3/8" thick. Bake in middle of oven until tops are puffed and pale golden, and cookies spring back when touched, 15 to 17 minutes. Transfer with a metal spatula to a rack cool about 5 minutes.

Frosting:
Stir together confectioners sugar, corn syrup, lemon juice, vanilla, and 1 tablespoon milk in a small bowl until smooth. Transfer half of icing to another bowl and stir in 2 tablespoons cocoa, adding more milk, 1/2 teaspoon at a time, to thin to same consistency as white icing and more cocoa to taste.

Frost the cookies:
Turn cookies flat sides up, then spread white icing over half of each and chocolate over other half. Use a pointed knife to make a straight edge.

Let the frosting set completely before storing. Stack cookies on parchment in an air-tight container. Refrigerate after a few days

Notes:
1. Set the butter out overnight to soften. Cut it to size first!
2. Set out the egg about a half hour before starting to get it to room temperature, which will help with the texture.
3. For the buttermilk, I put 1 tablespoon of lemon juice in a 1/3 cup container and added milk until full.
4. Be sure to use plenty of butter to grease the cookie sheets. And it's better to overcook than undercook because the flat sides need to be firm so that they don't come up and crumble when you frost them.
5. When I doubled my recipe, I just made the frostings separately and substituted water for the lemon juice for the chocolate frosting so that it did not have any lemon flavor.
6. I did *not* double the recommended 1/4 cup of cocoa powder, which is why I suggest starting with 2 tablespoons and adding more if needed. I used Valrhona cocoa powder and the frosting was amazing. Use good cocoa powder if you can.
7. To frost the cookies, I used the pointy butter knife that came with my silverware and got a perfect edge with it. Be sure to spread in only one direction so that crumbs from the cookie don't get mixed into the frosting (so start with just a little bit and at the edge). If your white edge isn't perfect, don't worry; the chocolate will cover it up.