Chocolate & Hazelnut Cake

When I posted this cake on my Instagram, ya’ll begged me for the recipe so here it is! It is a bit long, but the result is so worth it!

This is the cake I made for my boyfriend’s birthday and he claims it’s the BEST cake I have ever made. We were both so stunned by how good it was, ended up devouring the whole cake in 3 days.

It has two layers of a rich and dense chocolate sponge, filled with a chocolate and hazelnut mascarpone cream, and covered in a hazelnut praline buttercream.

Yield: One 2-layer 7″ cake

INGREDIENTS:

CHLOE’S ULTIMATE CHOCOLATE SPONGE-

• 340g Plain Flour
• 1tsp Baking Soda
• 2tsp Baking Powder
• 2tsp Salt
• 200ml Milk, warm
• 1/2 Lemon
• 200ml Hot Water
• 4tsp Instant Coffee
• 100g Cocoa Powder
• 400g Caster Sugar
• 80ml Vegetable Oil
• 2 Large Egg, room temp
• 2tsp Vanilla Extract

CHOCOLATE & HAZELNUT MASCARPONE CREAM FILLING-

• 1 Gelatine Sheet (1g)
• 100ml Double/Heavy Cream
• 1tsp Vanilla Bean Paste
• 85g Mascarpone Cream
• 1tbsp Powdered Sugar
• 2tbsp Chocolate and Hazelnut Spread (eg. Nutella)

HAZELNUT PRALINE SWISS MERINGUE BUTTERCREAM-

• 150g Hazelnuts
• 110g Caster/Granulated Sugar
• 40ml Water
• Pinch of Flakey Sea Salt
• 80g Egg Whites
• 150g Caster Sugar
• 1tsp Salt
• 1tsp Vanilla Extract
• 200g Unsalted Butter, softened

CHOCOLATE DRIP-

• 2 heaped tablespoons Nutella
• 1tsp Coconut Oil
• Crushed Rosted Hazelnuts

STEPS:

CHLOE’S ULTIMATE CHOCOLATE SPONGE-

1. Preheat the oven to 170°C and line two 7” cake tin with parchment/non-stick spray/butter
2. In a bowl, whisk together plain flour, baking soda, baking powder, and salt. Set this aside
3. Add the juice of 1/2 a lemon to the milk and let it curdle
4. In a large bowl, add hot water and 2tsp instant coffee. Let that dissolve then sift in cocoa powder. Whisk aggressively to remove any clumps
5. Then add the curdled milk mixture, sugar, oil, egg, and vanilla extract. Whisk until combined
6. Add the dry ingredient bowl (made in step 2) and whisk until just combined
7. Pour the batter evenly between the two tins 
8. Tap the cake tin against the counter to remove large air bubbles then give it a spin to allow the batter to spread along the sides of the tin
9. Pop them into the oven at 170°C for 30-40min. At 30min, check the tallest part of the sponge with a skewer. If it comes out clean, it’s done. If not, keep baking it until the skewer comes out clean.
10. Let in cool for 15min then transfer the sponge out of the tin and onto a wire rack to cool
11. Let it cool completely, then wrap it in some clingfilm and let it sit in the fridge overnight (the chocolate flavour will develop overnight and the texture will become so much better)
12. The following day, cut the tops off to level the cake layers, then wrap them up and place it into the freezer

CHOCOLATE & HAZELNUT MASCARPONE CREAM FILLING-

1. Fill a small container with cold water and ice cubes. Submerge the gelatine sheet into the cold water and set it aside
2. Combine double cream and vanilla bean paste in a saucepan. Transfer it onto a stove and heat the mixture until it starts to steam
3. Remove the pan from the heat. Pick up the gelatine sheet and shake off as much of the water as possible, then add it to the hot cream
4. Stir the cream until the gelatine is fully dissolved
5. In a bowl, add mascarpone cream and sugar, then pour the warm cream over the mascarpone cream. Gently whisk until everything is smooth
6. Cover the bowl with clingfilm then pop it into the fridge for at least 2hrs or overnight so it can set
7. Once the cream sets, use an electronic mixer and mix it up. Add the chocolate and hazelnut spread and whisk until its homogenous

HAZELNUT PRALINE SWISS MERINGUE BUTTERCREAM-

Start with the praline:

1. Gently roast the hazelnuts in a pre-heat oven at 200°C for 5-10min. Add the hot nuts in a tea towel and rub the nuts around to help remove the skin. Use your fingers to remove as much of the remaining skin as possible
2. In a saucepan, combine water and the 110g sugar. Transfer it onto a stove over medium heat and let it caramelize
3. Once it reaches a deep amble color, add all the peeled hazelnuts
4. Over medium heat, add the nuts and mix it with a spatula so the caramelized sugar is evenly distributed 
5. Spread the mixture evenly onto a sheet of parchment paper and sprinkle over a pinch of flakey sea salt. Let it cool completely
6. Once cooled, break it apart and add it to a blender/food processor. Blend it until the oils are released and it turns into a paste
7. Transfer it into an airtight container and store it in the fridge

Now the buttercream:

1. In a large bowl, combine egg whites, sugar, salt, and vanilla. Whisk well
2. Transfer the bowl onto a double boiler (saucepan with simmering water), then continuously whisk to let the heat dissolve the sugar and cook the eggs. The mixture will go from gloopy to runny. You want the sugar to be fully dissolved so rub the mixture in between your fingers to feel if there are any granules left. If not, remove the bowl from the heat
3. Using an electronic mixer with a whisk attachment, whip the mixture on high to help cool it down and turn it into a meringue. The mixture will become an opaque white and be able to hold its shape. Once it can hold medium to stiff peaks, you’re ready to move onto the next step
4. Feel the bowl to make sure it’s cooled back down to room temperature. If it is still warm you can pop it into the fridge or continue to mix it over an ice bath. Once it’s room temp, gradually mix in the softened butter
5. Scrape the bowl with the spatula and continue mixing for 10min. You should now have a delicious and fluffy buttercream
6. To remove all the air bubbles, pop the bowl into the microwave for 5-10secs. This should have GENTLY melted the buttercream, then aggressively mix it with a spatula to release the excess. You should now have a silky smooth mixture
7. Make the border buttercream: In a small bowl, add 2 heaping tablespoons of buttercream with 1 heaping tablespoon of the hazelnut praline. Gently whisk them together and set aside. For this, add as much of the praline as you would like
8. The rest of the buttercream: Add 1 heaping tablespoon of the praline into the rest of the buttercream and mix until combined. Add more if you desire more flavour or a deeper colour. DISCLAIMER: don’t add too much to this batch because the extra praline could disrupt the stability of the buttercream 

ASSEMBLE THE CAKE:

1. Add a small dollop of buttercream onto the centre of your cake board or turn table (this will act as glue for your cake)
2. Place the first frozen layer of chocolate sponge into the center and press it into place
3. Using the small batch buttercream with lots of praline, pipe a thick and tall border around the top of the cake
4. Add all of the Chocolate and Nutella Mascarpone Cream into the middle and spread it out to fill all of the space inside the buttercream border
5. Using the second layer of frozen chocolate sponge, flip it upside down so the cut side is on the bottom. Place it over the filling and press it into place
6. Pipe extra buttercream into any of the creavases that are empty. Then using a spatula, press all the buttercream into place and smooth out the sides
7. Crumb coat the cake: Add a big scoop of buttercream and spread it all over the cake. Smooth it out into a thin layer of buttercream with a offset spatula or bench scraper. This will lock in all the crumbs. Place the cake into the fridge
8. Take the remaining buttercream and microwave it for 5-10sec. Mix it around with a spatula and double check the consistency. The buttercream should not be too runny or split, but it should be a pourable consistency
9. Take the cake out of the fridge and pour the buttercream over the cake
10. Using an offset spatula, spread the buttercream evenly over the cake. Then smooth it out with a benchscraper. It doesn’t have to be perfect because we are covering it with chocolate

CHOCOLATE DRIP-

1. Lightly melt the nutella with coconut oil and stir to get a runny chocolate sauce
2. Pour it onto the center of the cake
3. Try to spread it out evenly on the top surface of the cake
4. Place the round tip of an offset spatula into the center of the cake at a 35° angle and start spinning the turn table. Keep the spatula steady and gently pull it towards the edge of the cake. This should give you a swirly patterned and let the chocolate drip down the sides organically
5. Add the crushed hazelnut on top in a circle

Final Steps:

1. Place the cake into the fridge and let the sponge slowly defrost incase the center is still frozen
2. Store the cake in the fridge, but take it out 1hr before consumption to allow the cake to come back to room temperature
3. It tastes best at room temp so enjoy!!!!