In a medium saucepan over low heat, combine heavy cream and granulated sugar. Stir until sugar dissolves and mixture is warm, not boiling. Whisk together semi-sweet chocolate and dark chocolate in a bowl. Pour warm cream mixture over and whisk until smooth. Refrigerate for at least 1 hour to set.

In a large bowl, whisk together all-purpose flour, cocoa powder, baking powder, baking soda, granulated sugar, dark brown sugar, and salt until evenly mixed.

Add eggs, vegetable oil, and hot coffee to dry mixture. Blend until smooth, about 2 minutes. Preheat oven to 350°F (175°C).

Divide batter between two greased 9-inch round cake pans. Bake for 30-35 minutes. Let cool in pans for about 10 minutes before transferring to wire racks.

While cakes cool, mix brewed coffee and cocoa powder in a bowl until dissolved; allow to cool to room temperature.

Level the tops of the cakes if needed, slice each cake horizontally to create layers. Soak the top of one layer with coffee mixture, spread frosting, then stack the second layer on top.

Apply a thin crumb coat around the cake and refrigerate for 20 minutes. Frost the top and sides with chilled espresso fudge frosting.