Black Vintage Heart Cake

A gorgeous, deep black cake made with chocolate cake, raspberries, and black swiss meringue buttercream

Prep Time 3

Rest Time 1 30

Course Dessert

Cuisine American

227g egg whites (about 7 large egg whites)
454g (2 1/4 cups) granulated sugar
680g (48 tbsp, or 6 standard sticks) salted butter, softened but not fully room temperature
90g (3/4 cup) black cocoa powder
black gel food dye, or black powder fat soluble food dye

Preheat the oven to 350F and line your half sheet tray with parchment paper
Whisk together flour, sugar, cocoa powder, espresso powder, baking soda, baking powder, and salt
In a separate large bowl, whisk together sour cream, oil, eggs, and buttermilk until combined
Sift the dry ingredients into the wet ingredients Add the hot water or coffee. Whisk gently until just combined.
Pour into your baking tray. Place in the middle rack of the oven and bake for about 20 - 25 minutes until a toothpick comes out clean
Let cool completely before removing from the pan. To remove, run a knife along the edges of the pan, then turn upside down onto a clean surface and peel off the parchment paper
Cut out a heart-shaped stencil from a piece of paper. Make sure that the stencil is sized so that you can cut 3 heart pieces out of the sheet tray. If you can't fit 3 pieces perfectly, you can use scraps to piece together one of the layers. Just make sure it's in the middle of the cake.
Cut out the heart-shaped cake layers. Wrap in plastic, and place in the freezer until firm, at least 1 - 2 hours.

Place your egg whites and sugar into the mixing bowl of your stand mixer
Bring 2 inches of water to a boil in a small pot, then reduce heat to low so the water is simmering. The mixing bowl with the egg whites should be able to rest on the pot, without the bottom touching the water. Place the bowl on top of the pot, and whisk the egg whites and sugar until the sugar dissolves. When you rub the whites between your fingers, you should not feel any granules of sugar
Use a whisk attachment to whip the egg whites on high to stiff peaks
Reduce speed to low, and slowly add small pieces of the softened butter. The butter should be soft, but still a little firm. If it's too warm, the buttercream will curdle. Keep mixing until the buttercream is homogenous
Remove and reserve a small amount for piping words later on
Add the black cocoa powder and black food dye
Increase speed to high, and whip until everything is homogenized. Take 1/4 of the buttercream, and microwave for 10 - 15 seconds until melted. You should see the black color intensify. Add more black gel dye to the microwaved buttercream if needed
Add the warmed up buttercream back to the main batch, and whip on high until light and fluffy. The color should be a dark charcoal at this point. It's okay if it's not completely black
Let the buttercream sit for a few hours or overnight for the color to darken to a true black. If it has cooled down and solidified, whip it back up before frosting

Remove the cake from the freezer, and place one layer on a cake board on a rotating cake stand
Pipe on a layer of butter cream. Cover with raspberries, and spread with a thin layer of additional buttercream
Place another layer of cake on top. Repeat piping on a layer of buttercream, raspberries, and more buttercream
Place the final layer of cake on top. Cover the entire cake with a thin layer of buttercream to seal in any crumbs. Place in the freezer for at least 20 minutes so that the crumb coat sets up
Use an offset spatula to put a final layer of buttercream on the cake. Smooth out the sides with a bench scraper
Use the piping tips to pipe the design. I do a top and bottom border with the large French star tip, and smaller accent borders with the small round tip. To make drapes on the sides, I cut a small hole in the piping bag.
Use the white buttercream you saved from earlier to pipe on any words
Store in the fridge, and bring out to room temperature 1 - 2 hours before serving. Letting the cake come to room temperature will further intensify the black color

A lot of cake making is managing timing. I recommend spreading the process over 2 days:

Day 1 - make the cake layers, and make the buttercream. Freeze the cake layers overnight, and let the buttercream rest so that the color intensifies
Day 2 - whip the buttercream back up, and assemble the cake

Keyword cake, chocolate