Chocolate cake and coffee buttercream come together in this cake worthy of any celebration. Topped with dark chocolate ganache, it’s a guaranteed show-stopper.
Every year as my husband’s birthday looms closer, I hand him a few of my cookbooks and tell him to pick out the cake he wants. I’ve had mixed success recreating his choices over the years— there was this incredible chocolate cola cake with toasted coconut and pecan icing, but there was also this failure of a chocolate peanut butter cake.
Thankfully, this year’s creation goes in the huge success column.
Steve chose this stunning chocolate coffee layer cake with chocolate ganache from Baked Explorations, one of my favorite baking cookbooks. I don’t know how I’d missed it before.
The cake is a simple and super moist chocolate sour cream cake. The coffee buttercream is a bit labor-intensive but well worth the effort— light, creamy and subtly scented with coffee. The ganache is the literal and proverbial icing on the cake, and it ties it all together beautifully and deliciously.
Heavy on the chocolate and light on the coffee, this cake will be loved by everyone, not just coffee lovers.
After dinner and a movie with my husband, we came home and sliced into the cake and oohed and ahhed through every bite. Birthday cake success!
A few notes about this recipe:
- When making the cake, it’s very important that you sufficiently cream the butter and sugars together before proceeding. It affects both the rise and texture. If you’re not sure what you’re looking for, check out my tutorial on The Creaming Method.
- The buttercream recipe is a bit unusual at first glance, but it is actually a variation on Swiss or Italian Meringue Buttercream. Butter is whipped into a pseudo pastry cream, creating a frosting that is light and dreamlike.
- The success of the buttercream is largely determined by the temperature of the butter. It should be at room temperature and soft enough that your finger will leave an imprint when pressed, but not so soft that your finger easily presses through it.
- If the buttercream is liquidy after you’ve added all the butter, try chilling it in the fridge in 10 minute intervals to stiffen the butter. After 10 minutes, try beating it again. If necessary, chill for another 10 minutes.
- I baked this cake in two 8-inch by 3-inch pans. If your cake pans aren’t 3 inches deep, use three or more cake pans to avoid overfilling them.
- To create the perfect drips of ganache down the sides, work with small amounts of ganache at a time. Use a small spoon to encourage it over the side in regular intervals (instead of just pouring a lot on and letting it drip down on its own).
- For more tips and tricks on baking and icing a cake, see my tutorial on How to Build a Layer Cake.
Chocolate Coffee Layer Cake
For the chocolate cake:
- ¾ cup unsweetened cocoa powder (65 grams)
- ⅔ cup sour cream (150 grams)
- 1 ¼ cup hot coffee or water (296 ml)
- 2 ⅔ cup all-purpose flour (320 grams)
- 2 teaspoons baking powder
- 1 teaspoon baking soda
- ½ teaspoon salt
- 1 ¼ cup unsalted butter , at room temperature (280 grams)
- 1 cup packed light or dark brown sugar (215 grams)
- 1 ½ cups granulated sugar (300 grams)
- 3 large eggs
- 1 tablespoon vanilla extract
For the coffee buttercream:
- 1 ½ cup granulated sugar (300 grams)
- ⅓ cup flour (40 grams)
- 1 ¼ cup whole milk (295 ml)
- ⅓ cup heavy cream (80 ml)
- 2 tablespoons instant espresso powder
- 1 ½ cups unsalted butter , at room temperature and cubed (340 grams)
- 1 tablespoon vanilla extract
For the ganache:
- 8 ounces dark chocolate , chopped or use chips (227 grams)
- ¾ cup unsalted butter , cubed (170 grams)
- 1 tablespoon light corn syrup
To make the chocolate cake:
- Preheat oven to 325°F. Line two 8-inch by 3-inch round cake pans (see Note) with parchment paper and grease with non-stick cooking spray or coat with butter and flour.
- In a medium bowl, whisk together the cocoa, sour cream and hot coffee or water until smooth. Set aside to cool.
- In a separate bowl, combine the flour, baking powder, baking soda, and salt.
- In the bowl of stand mixer fitted with a paddle attachment, beat the butter and sugars together on medium high speed until very light and creamy, scraping the bowl down as necessary, about 5-7 minutes. Add the eggs one at a time, mixing after each. Add the vanilla.
- Add the flour mixture in 3 additions, alternating with the cooled cocoa mixture, ending with the flour mixture. Mix until just combined. Divide the batter equally between the prepared cake pans.
- Bake, rotating halfway through. until the center of the the cakes bounce back when touched and a toothpick inserted into the center comes out with a few moist crumbs, about 40-45 minutes. Let cool in the pans for 10 minutes, then remove to a wire rack to cool completely.
To make the coffee buttercream:
- Whisk together the sugar, flour, milk, heavy cream and espresso powder in a medium saucepan. Set over medium heat and bring to a boil, stirring occasionally. Continue to cook, stirring constantly, until mixture is thickened, about 8-10 minutes.
- Pour mixture through a mesh strainer into the bowl of a stand mixer fitted with a paddle attachment. Beat on medium high speed until cooled to room temperature, about 10 minutes.
- Reduce the mixer speed to medium and add the cubed butter a tablespoon at a time, letting it become incorporated before adding the next tablespoon. Once all the butter has been added, add the vanilla and beat on high speed until buttercream is thick and creamy. If buttercream is too soft, chill in the fridge for 10 minutes, then try beating again.
To assemble the cake:
- If desired, cut the cooled cake layers in half, creating 4 layers. Place the first cake layer on a cake stand or plate. Cover with ¾ cup of the buttercream and top with another cake layer. Repeat.
- Cover the layer cake with a thin layer of buttercream to create a crumb coat. Chill cake for 10 minutes to set, then cover with remaining buttercream. Chill for at least 30 minutes.
To make the ganache:
- Place the chopped chocolate, cubed butter, and corn syrup in a large heat-proof bowl set over a pan of barely simmering water. Stir as mixture melts. Once smooth, remove from heat and let cool for about 5 minutes.
- Pour about ½ cup of the ganache over the top of the chilled cake, spreading it just to the edge without letting it spill over the sides. Chill 5 minutes. Pour another ½-1 cup of the ganache over the cake, this time pushing it over the sides and letting it drip down. Let cake set for 30 minutes at room temperature or 10 minutes in the fridge before serving.
- If your cake pans aren't 3 inches deep, it's best to use 3 or more cake pans.
- If desired, top with chocolate covered coffee beans for decoration.