Double Dark Chocolate Cake with Black Velvet Icing (adapted from Alexandra Cooks)
*High altitude adjustments given in italics*
3 oz semisweet chocolate, chopped
1 1/2 cups hot brewed coffee (or boiling water with 1 tsp espresso powder)
1 1/2 cups unsweetened cocoa powder *See Note*
3 cups sugar (minus 3 Tb)
2 1/2 cups all-purpose flour (plus 1-2 Tb)
2 tsp baking soda
3/4 tsp baking powder (skip the baking soda, use 1 1/4 tsp baking powder)
1 1/4 tsp salt
3 large eggs (4 large eggs)
3/4 cup vegetable oil
1 1/2 cups buttermilk
1 tsp vanilla
*Note: To get this crazy deep black color, use Hershey's Special Dark cocoa powder, or dutch-procesed. However, I find that if you use ALL dark cocoa powder, it becomes bitter, so I used 1 cup dark cocoa and 1/2 cup regular cocoa.*
Preheat oven to 300 degrees (315 degrees for high altitude) and grease two 9 inch cake pans. Line the bottoms with parchment paper and lightly grease the parchment. Set aside.
Place the chopped chocolate in a medium bowl with the cocoa powder (and espresso powder, if using). Pour hot coffee/water over the chocolate and cocoa, and stir until melted and smooth. Set aside.
In a large bowl, whisk sugar, flour, baking soda, baking powder, and salt together, and set aside.
Beat eggs until lightened in color and thickened slightly (about 3-5 minutes). Slowly add oil, buttermilk, vanilla, and melted chocolate mixture to eggs, beating until well combined. (Test the chocolate first: if it is still hot, stir in some of the buttermilk to cool it before adding to the eggs). Add dry ingredients and beat on medium speed until just combined. Divide batter between pans and bake in middle of oven until a tester inserted in center comes out clean, 1 hour to 1 hour and 10 minutes. Start checking at 50 minutes, check often, and be careful not to overbake! While your cake is baking, make your awesome icing!
Black Velvet Icing:
4 oz semi-sweet chocolate
1/3 cup powdered sugar
3 eggs, well beaten
4 Tb butter, room temperature
In a small saucepan over low heat, melt the chocolate. Add about a third of the sugar, and whisk until smooth. Add half of the beaten eggs, whisking constantly, until combined. Repeat with the next third of sugar, last half of the eggs, and remaining sugar, whisking until smooth after each addition. Stirring constantly, cook until the mixture thickens and the whisk leaves trails. Stir in the butter one tablespoon at a time. Mixture should resemble cake batter. Transfer to a bowl or pour-able measuring cup to cool.
When your cake is finished baking, transfer to wire racks and let cool completely in the pans. Cake layers may be made 1 day ahead and kept, wrapped well in plastic wrap, at room temperature.
To assemble: carefully sliced the domed tops off of one or both of the cake layers. Place one layer, cut side down, on a serving plate. Spread with about half of the icing, almost to the edge. Place the other layer, flat (or cut) side down (you can leave a dome on the top layer if you'd like!) and spread the remaining icing over the top, allowing the excess to fall down the sides.