Dark chocolate cake with raspberry buttercream and chocolate hazelnut ganache
I used to bake much more than I cooked. Baking is precise, a little variation in ingredient quantities and you could get unexpected and undesired results. Cooking is more intuitive, and measurements to me are suggestions, I usually do not measure my spices at all. When I had less confidence in my culinary skills, baking was my comfort zone, because if you could follow instructions exactly, you would get good results. My daughter’s birthday was the perfect occasion to make a nice cake. Her requests were dark chocolate and raspberry, and I know that she also loves hazelnuts. So I looked up some recipes, but all fell short on something in my opinion, so I decided to create what I was envisioning. Despite some difficulties (the buttercream was not coming together at first) and a little room for improvement (2 of the 3 cakes were a tiny bit uncooked in the center), the end result turned out to be very moist and delicious. Oh yes, I should also let you know that I always use less sugar in my baked goods, so if you want to make it sweeter, just add a bit more sugar.
Yield: 12-14 slices
Prep time: 45 minutes
Cook Time: 45 minutes
Total time: 90 minutes
Dark Chocolate Cake:
2 1/2 cups all-purpose flour
1 1/4 cup sugar
3/4 cup dark cocoa powder
2 teaspoons baking powder
2 teaspoons baking soda
1 teaspoon salt
2 large eggs (at room temperature)
1 cup buttermilk
1 cup vegetable oil
1/2 cup brewed coffee or espresso
1/2 cup boiling water
1 1/2 tablespoon vanilla extract
5 large egg whites
3/4 cup sugar
1 1/2 cups unsalted butter (3 sticks) [at room temperature]
2 teaspoons vanilla extract
1/4 cup buttermilk
1 cup fresh raspberries (plus a handful for decoration)
pinch of salt
Chocolate Hazelnut Ganache:
4 ounces bittersweet chocolate (I used Callebaut)
4 ounces hazelnut chocolate (I used Callebaut)
2/3 cup butter (at room temperature)
How is this sustainable?
Many of my ingredients are sustainably sourced — eggs from a local chef-owned farm, organic and local buttermilk, unbleached flour and sugar, organic raspberries, and socially just chocolate.
Dark Chocolate Cake:
- Preheat oven to 300° F.
- Line 3 9″ round baking pans with parchment paper (I had run out, and in a pinch you can use aluminum foil, shiny side up, and greased with butter — don’t forget the sides) and set aside.
- Combine flour, sugar, dark cocoa powder, baking powder, baking soda and salt in the bowl of a stand mixer.
- Add eggs, buttermilk and vegetable oil, and mix in stand mixer with the flat beater installed.
- Add hot coffee or espresso and vanilla extract to boiling water.
- Add to the mixture and mix well. The batter will be quite thin.
- Divide batter evenly between the 3 cake pans and bake for 35-40 minutes (the cake is done when a toothpick inserted in the middle comes out clean).
- Remove cakes from oven and let them cool completely.
- While the cake is cooling, you can get started on the buttercream.
Raspberry Swiss Meringue Buttercream:
- Wash raspberries and let them dry completely.
- Wash the mixer bowl and attachments. Here is a neat trick I learned — put some lemon juice on a paper towel and then wipe out your mixer bowl with it before making the meringue — this removes any trace of grease in the bowl.
- Add egg whites and sugar to the bowl and then whisk them constantly and gently over a simmering pot of water until the sugar has completely dissolved and the egg whites are hot.
- With the whisk attached to the stand mixer, whip the hot mixture until the meringue is thick and glossy, and — this is very important — the bottom of the bowl has reached room temperature. This process takes about 10 minutes.
- Roughly puree the raspberries with a blender or food processor.
- Cut the butter into cubes.
- Method 1: Switch over to the flat beater attachment, start mixing on slow speed and add the butter one cube at a time. Keep running at slow speed until the mixture has reached a silky smooth texture (if it curdles, keep mixing and it will smooth back out*). Add vanilla, buttermilk, salt, and finally the pureed raspberries while continuing to mix.
- Melt chocolate and butter in a double boiler (I simply use a metal bowl over a simmering pot of water) and stir with a rubber spatula until smooth.
- Cut the domes off two of the cooled down cakes with a serrated knife (a perfect snack for the baker…).
- Put the first cut layer down on a cake plate and spread a layer of butter cream evenly on top.
- Put the second cut layer on top and spread another layer of butter cream evenly on its top.
- Put the final cake layer on top, and then cover the top as well the sides of the cake with butter cream evenly.
- Put slightly cooled ganache into a pastry bag with a thin tip or a decorating bottle fitted with a thin tip and decorate the cake with it (I used it to write Happy Birthday Katia on mine). Make sure you have some ganache drizzling down the sides as well.
- Use the remaining whole raspberries to finish decorating the cake.
*The completion of the butter cream proved to be the most frustrating for me — after having made the most fantastic meringue, the mixture curdled and never did turn back to smooth. Impatiently, I had even added the vanilla, salt, and raspberries to it. All likely because not all my butter had been at room temperature yet, so I cheated and used 1/3 room temperature and 2/3 cold butter. A quick google search for curdled buttercream didn’t sound very hopeful. One thing I tried was to add about a 1/4 cup of buttermilk to the mixture. The resulting butter cream was quite delicious, so I kept that as part of the recipe — and you already have it on hand for the cake. My final solution was to transfer the lumpy mixture to the food processor with the dough blade installed, and about a 10 minute run in there made it into a lovely smooth-textured butter cream. Next time I make a butter cream, I think I will retire the mixer right after the meringue is done and finish the butter cream in the food processor.