These cookies were given to Patsy's paternal aunt, Lena Manley Flanagan, in the early 1930s by the lovely Regina Nelson. The Nelsons and Manleys have remained family friends for four generations. The cookies were made fairly often, as Patsy usually requested anything chocolate. These double-chocolate cookies have a shiny chocolate icing and are superb with or without nuts. Chocolate Cloud Cookies were truly a find because we have never tasted anything like it. This cookie simulates chocolate air. We paired it with a rich fudge frosting: The combination of light and dense makes for a uniquely scrumptious delight. Place an espresso bean on top of each cookie after icing for visual effect.
Place the sugar and butter in the bowl of a stand mixer fitted with the paddle attachment and beat on medium speed until creamy. Reduce the speed to low and add the egg and vanilla. Add the melted chocolate and mix until smooth. Add half of the flour mixture and blend. Slowly incorporate the milk mixture. Add the second half of the flour mixture and blend until smooth.
Drop the dough by heaping teaspoonfuls onto the baking sheet, leaving at least 1 inch between cookies. Bake for 8 to 10 minutes, until the cookies spring back when touched. Make the frosting while the cookies bake. Remove the cookies from the oven and cool for 1 minute.
Lift the edges of the parchment paper and transfer the entire sheet of cookies (still on the paper) to a wire rack. If you did not bake the cookies on parchment paper, place wax paper on the rack to keep the frosting from dripping all over, and transfer the cookies individually. While the cookies are still warm, drizzle a teaspoon of the chocolate frosting on each and use the back of a spoon to spread the icing around.
We like to keep some of the underlying cookie exposed because it is so unusual. Let cool until the frosting sets.
Place the chocolate and butter in the top of a double boiler (or in a metal bowl nestled in a saucepan of boiling water) over medium heat, stirring regularly. When the chocolate is melted,
stir in the sugar. Add the hot water, 1 tablespoon at a time, mixing until smooth. Remove from the heat and gently mix in the egg yolks, vanilla, and salt, stirring after each addition. Blend with a handheld electric mixer on low speed (or by hand) for 1 minute, or until the frosting is smooth. If the frosting is too thick to pour, add more hot water, a little at a time, to achieve a consistency
that allows for drizzling.