8 ounces of bittersweet chocolate, very finely chopped
1 cup of very hot brewed coffee
½ cup of buttermilk or sour milk
1 teaspoon of vanilla
4 cups of all-purpose flour
½ cup of unsweetened cocoa powder
1 teaspoon of salt
¾ teaspoon of baking powder
½ teaspoon of baking soda
1 ½ cup of unsalted butter, softened
3 cups of granulated sugar
¾ cup of canola oil
6 egg whites
1 ½ cups of granulated sugar
2 tablespoons of light-color corn syrup
pinch of salt
Preheat oven to 350 degrees F. Grease a 13x9x2-inch baking pan. Line the bottom of the pan with parchment paper; grease the paper and flour the pan. Set pan aside.
In a medium bowl stir together the flour, salt, baking powder, and baking soda; set aside. In a large mixing bowl beat butter and sugar with an electric mixer on high speed until light and fluffy, about 3 minutes. Scrape down the sides and add the oil.
Mix until combined. Add the eggs, one at a time, scraping down the sides and bottom of the bowl between additions. Alternately add the flour mixture and buttermilk, mixing on low to medium speed until a smooth batter forms. Transfer the batter to the prepared pan, spreading evenly. Bake for 25 to 30 minutes or until the top springs back when lightly touched. Cool in pan on a wire rack. Cover with plastic wrap and freeze at least 30 minutes.
Preheat oven to 350 degrees F. Coat a 10-inch tube pan with nonstick cooking spray for baking; set aside. Place the finely chopped chocolate in a medium heat-proof bowl and pour the hot coffee over the chocolate; do not stir. Allow to stand 2 minutes. Whisk until smooth; cool. Stir in buttermilk and vanilla; set aside. In a large bowl whisk together the flour, cocoa powder, salt, baking powder, and baking soda. Whisk at least 30 seconds to distribute the leavening well; set aside.
In a very large mixing bowl beat butter and sugar with an electric mixer on high speed for 2 minutes until well-combined and smooth, scraping bowl occasionally. Scrape down the sides and bottom of the bowl and add the oil. Beat for 2 minutes more. Add the eggs, one at a time, beating well after each addition. Alternately add the flour mixture and the coffee mixture on medium-low speed until fully incorporated. Beat on medium to high speed for 20 seconds more.
Using a 3-inch snowman cookie cutter, cut out about 12 to 15 snowmen from the cold sheet of vanilla cake.
Spread about ½ of the chocolate batter into the prepared tube pan. Gently place the snowmen cutouts, head down, into the batter, spacing them about ½-inch apart. Fill a pastry bag fitted with a large open round tip with some of the remaining chocolate batter and pipe or gently spoon batter all around the snowmen to keep them evenly spaced apart. Gently spoon the remaining batter to within 1-inch of the top of the pan over the snowmen and spread gently to cover, being careful not to disturb the snowmen. Place the pan with batter on a foil-lined baking sheet. (Use any remaining batter for cupcakes, spooning ¼ cup batter per paper bake cup-lined 2 ½-inch muffin cup. Bake for 18 to 20 minutes or until toothpick inserted in centers comes out clean.)
Bake tube cake for 1 hour, 20 minutes or until a long skewer inserted near the center of the cake comes out clean. Cover the cake loosely with foil, if necessary, during the last 15 minutes of baking to prevent overbrowning. Remove and cool in the pan for 15 minutes on a wire rack. Loosen sides and around the tube and invert with the bottom side up onto the wire rack. Remove pan. Cool completely.
Combine the egg whites, sugar, corn syrup and salt in a large heat-proof stainless steel mixing bowl. Set the bowl over a large saucepan with simmering water (the bottom of the bowl should not touch the water). Beat with an electric mixer on high speed until light and fluffy and an instant-read thermometer inserted in the mixture registers 160 degrees F (this should take about 10 minutes). Remove the bowl from the saucepan. Continue beating until stiff peaks form. Using a small offset spatula, swirl topping all over the top and sides of cooled cake and over any cupcakes.