1Preheat oven to 320 degrees Fahrenheit.
2Grease 2 (8"x12") baking pans.
3Chocolate Cake Preparation:
4Melt chocolate, butter, sugar, and water over low heat. Pour the mixture into a bowl. Let cool for 10 minutes.
5Whisk in sifted flour and cocoa, then add the egg yolks. Divide the batter into the pans, bake for 25 minutes. Cool.
6Using a round cookie cutter, cut 12 circles in each cake.
7Chocolate Ganache Preparation:
8Bring the cream to a boil and remove from heat. Add chocolate and stir until it melts. Let cool.
10Beat the butter, brown sugar, and eggs in a bowl. Stir in the flour, and then the cocoa. Knead the dough on a working surface. Divide in half and roll each piece of dough between 2 sheets of wax paper. Refrigerate for 30 minutes.
11Preheat oven to 350 degrees Fahrenheit.
12Using a round cookie-cutter cut out 48 circles of dough.
13Bake cookies for about 12 minutes.
15Spread the ganache on the back side of the cookies and add a slice of cake between the two cookies.
16Place a heart shaped stencil on top of the cookies and sprinkle with cocoa.