Fudgy Chocolate Nutella Cake
A chocolate hazelnut lover's dream cake: layers of fudgy and decadent chocolate cake with creamy Nutella ganache filling and Nutella buttercream frosting. I love using the Nutella ganache as a drip for the perfect finishing touch!
Servings 15 slices
Ingredients
Fudgy Chocolate Cake
- 2 Cups (265g) all-purpose flour
- 1 2/3 Cups (340g) granulated sugar
- 2/3 Cup (60g) unsweetened cocoa powder Dutch-process or regular
- 2 tsp baking soda
- 1 tsp baking powder
- 1/2 tsp salt
- 1/2 Cup (120ml) vegetable oil
- 2 large eggs, room temperature
- 3/4 Cup (180g) sour cream, room temperature
- 1 1/2 tsp pure vanilla extract
- 1/2 Cup (120ml) buttermilk*, room temperature DIY recipe in notes
- 1/2 Cup (120ml) hot coffee or hot water
Nutella Ganache
- 1 Cup (300g) Nutella
- 3/4 Cup (180ml) heavy whipping cream
Nutella Buttercream
- 1 1/2 Cups (339g) unsalted butter, room temperature
- 5 Cups (600g) powdered sugar
- 3/4 Cup (225g) Nutella
- 1 Tbsp pure vanilla extract
- 3 Tbsp whole milk, room temperature
- 1/4 tsp salt, or to taste
Garnish (optional)
- chocolate hazelnut candy bar, chopped finely for sprinkling on top
Instructions
Make the Fudgy Chocolate Cake
- Preheat the oven to 350ºF/177ºC and prepare three 6-inch or two 8-inch cake pans by spraying the sides with cooking spray and fitting the bottoms with a parchment paper circle.
- Place all of the dry ingredients into the bowl of a stand mixer fitted with the paddle attachment (or with a large bowl and hand mixer) and mix on low for 30 seconds to fully combine them. Add the vegetable oil, eggs, sour cream, vanilla, and buttermilk and mix on low until just combined. With the mixer still on low, add the hot coffee in a slow stream. Continue mixing on low until fully combined, 1-2 minutes. The batter will be very thin.
- Pour the batter into the prepared cake pans and bake for 32-36 minutes, until a wooden toothpick inserted comes out clean. Cool completely before frosting.
Make the Nutella Ganache
- Measure the Nutella into a heat resistant bowl (glass or metal) and set aside. In a saucepan over medium-high, heat the heavy whipping cream until it begins to simmer, whisking constantly.
- Once the cream begins to simmer, remove the pan from the heat and pour the cream over the Nutella. Let it sit for about 30 seconds before whisking together until the consistency is uniform and well blended. Let it cool to room temperature before using as a cake filling or dripping the cake.
Make the Nutella Buttercream
- With a paddle attachment on your stand mixer (or using a large bowl and hand mixer), cream the butter on medium-high until it’s creamy and light in color, about 5 minutes.
- Add the powdered sugar a few cups at a time, scraping down after each addition and making sure each cup is fully incorporated before adding the next one. Add the Nutella and beat on med-high speed for a full minute. Scrape down the paddle once more.
- Turn the mixer to low speed and add the vanilla, milk, and salt. Mix for another 1-2 minutes, scraping down the bowl and paddle as needed, until smooth and fully incorporated.
Assembly
- Once the chocolate cake layers have cooled completely, level and torte each layer to your desired height. Place the first layer on a turntable and pipe a circle of Nutella buttercream (aka a buttercream dam) around the edge. Fill the dam part way with (room temperature!) Nutella ganache, then fill in the rest of the space with more Nutella buttercream. Here's a detailed tutorial on this filling method.
- Place the next cake layer on top and repeat the process of piping the buttercream circle and filling in the center with Nutella ganache and Nutella buttercream. Place the final layer on top, upside down so that the bottom of the cake layer is the top of the cake. Crumb coat the cake with Nutella buttercream and place it in the refrigerator for at least 20 minutes to let everything set up.
- To create the cake design pictured, frost a smooth layer of Nutella buttercream around the cake, then place it back into the refrigerator for 20-30 minutes to create a cold foundation for the Nutella ganache drip.
- Meanwhile, prepare the Nutella ganache drip: if it's too thick for dripping the cake, microwave it in 5-10 second increments until it's room temperature and good drip consistency (this post shows examples of perfect drip consistency). When the cake is nice and chilled and the Nutella ganache is perfect drip consistency pour about half of the remaining ganache on top of the cake, then use an angled spatula to gently push it over the edges of the cake and create the curtain drip. Place it back into the refrigerator for 5-10 minutes to let the Nutella ganache drip set.
- Fit a piping bag with Wilton Tip 4B and fill it with the remaining Nutella ganache, then pipe swirls on top of the cake. Sprinkle with chopped hazelnuts or a chopped hazelnut chocolate bar, if desired.
Notes
*DIY Buttermilk recipe: add 1 Tbsp of white vinegar to a jar and top it with 1 Cup of whole milk. Stir and let sit for 15 minutes before using in the recipe.
Make Ahead Tips:
- The chocolate cake can be made ahead and stored at room temperature, covered tightly in plastic wrap, for up to two days. Alternatively, you can cover with plastic wrap and store in the freezer for up to two months before thawing to room temperature.
- The Nutella ganache can be made ahead and stored in an airtight container for up to two weeks in the refrigerator. When you’re ready to use it, heat the ganache in the microwave in 15 second intervals until it’s room temperature again.
- The Nutella buttercream can be made ahead and stored in an airtight container at room temperature for one day. Alternatively, you can store it in an airtight container in the refrigerator for up to two weeks. When you’re ready to use it, bring it back to room temperature and re-mix with your stand mixer on low speed to bring it back to piping/frosting consistency.