BLACK AND WHITE COOKIES...THE BEST RECIPE!!!!

Black & White Cookies (recipe adapted from Baked Explorations)
Cookies
3 cups all purpose flour
1/2 tsp baking soda
1/2 tsp baking powder
1/2 tsp salt
1 3/4 sticks of unsalted butter, soft
1 1/4 cups granulated sugar
2 large eggs
1 large egg yolk
3/4 cup buttermilk
1 T pure vanilla extract

Frosting
3 3/4 cups confectioners' sugar
4 to 5 T whole milk
3 T heavy cream
2 tsp pure vanilla extract
1/2 cup plus 2T. Nestle or Hershey unsweetened cocoa powder
Preheat the oven to 350. Line baking sheets with parchment paper.  In a large bowl, mix the dry ingredients for the cookies (flour, baking powder, baking soda and salt).  In the bowl of a stand mixer fitted with the paddle attachment, cream the butter and sugar until fluffy, about two minutes. Add the eggs and the yolk, one at a time and mix.  Add the flour mixture in three parts, alternating with the buttermilk (begin and end with flour). Add the vanilla . 
Using a 1/4 cup scoop, drop the dough on the prepared baking sheets or use a muffin top pan as I did. 
Bake for 17 minutes, baking each sheet one at a time. Edges should be lightly browned.  Allow to cool completely before frosting.

To make the frosting, in a large bowl, whisk together the confectioners' sugar, milk, cream and vanilla. If the mixture is too thick, add milk by the teaspoon. Divide in half and add the chocolate powder to half of the mixture. Add a bit of milk by the teaspoon if you need to thin the chocolate a little bit.  I needed to thin it quite a bit.  Using a spatula, frost one half vanilla and allow to dry 20 mins. before frosting the other half with the chocolate glaze.  Let the frosted cookies set for one hour before serving.