My girlfriend is obsessed with chocolate, and anything containing it instantly becomes the best thing I’ve cooked in any given week. I therefore started baking a Nutella cake for her birthday. But I also wanted to use feuilletine (crêpes baked until crispy then shattered); without textural contrast, I often find cakes a bit one-note. Then, having decorated the outside with something which was present on the inside, toasted hazelnuts, I realised I’d unwittingly made a cake which was more Ferrero Rocher than Nutella. Of course, given that they’re both manufactured by Ferrero and Ferrero Rocher is filled with Nutella, this was no great leap. Fun fact: 30% of the world’s hazelnut supply is used by Ferrero!

I learned the hard way while making last year’s cake that feuilletine does not stay crispy when simply covered by chocolate ganache; mixing with melted chocolate and nut paste as I’ve done here is one method of retaining that crunch. I didn’t have enough hazelnuts on hand, so the nut paste ended up including a bit of whatever I had in the larder (almonds and cashews). It seemed to work well regardless! The cake also features a Swiss meringue buttercream, which somehow manages to be light and airy in texture while tasting incredibly rich. Next time, I think I’ll try making more crushed hazelnuts and using them to cover the sides of the cake.

The cake base is BraveTart’s incomparable Devil’s Food Cake.

Ingredients

• 150g double cream
• 400g Nutella
• 230g dark (70%) chocolate
• 12 large egg whites
• 400g caster sugar
• 890g unsalted butter
• 340g black coffee, freshly brewed
• 85g Dutch-process cocoa powder
• 455g brown sugar
• 15g vanilla extract
• 4g table salt
• 255g plain flour
• 13g baking soda
• 200g hazelnuts
• 40g white chocolate
• 80g feuilletine
• 1 cake round
• 6 Ferrero Rochers

Method

1. Preheat oven to 180°C
2. Make ganache: heat double cream til just bubbling, then pour hot cream over 200g Nutella and 60g chocolate in heatproof bowl
3. Leave ganache for 5 mins then mix until combined and refrigerate
4. Meanwhile, make Swiss meringue buttercream: in large, metal or glass bowl, separate 6 egg whites and add caster sugar
5. Using electric whisk, beat egg whites over bain marie until they reach 70°C, then remove from heat and continue whisking until stiff peaks form
6. Add 550g unsalted butter and remaining 200g Nutella then continue beating until incorporated
7. Transfer buttercream to piping bag and refrigerate
8. Meanwhile, make cake: line 3 20x8cm cake pans with baking parchment
9. Combine hot coffee and remaining 340g butter in metal bowl, mixing until homogenous (adding gentle heat if necessary)
10. Add remaining 170g dark chocolate and cocoa powder, mixing until homogenous (adding gentle heat if necessary)
11. Add brown sugar, vanilla extract, salt, remaining 6 whole eggs and 3 egg yolks, beating to combine
12. Fold in flour and baking soda then divide between lined pans
13. Bake until cakes are firm and a toothpick can be inserted and removed with a few crumbs attached
14. Cool cakes for 1 hour, then invert onto wire rack, remove parchment and return cakes right side up
15. Meanwhile, prepare feuilletine crunch: roast hazelnuts at 180°C until skins easily slip off and they are starting to brown
16. Blend 160g hazelnuts (adding as much vegetable oil as necessary) to form paste
17. Melt white chocolate and mix into hazelnut paste and feuilletine
18. Crush remaining 40g hazelnuts
19. Level cake bases
20. Assemble cake: pipe a little buttercream to stick cake round on cake turntable, then a little more to stick first cake layer (right side up) on turntable
21. Pipe buttercream ring around perimeter of cake
22. Spread layer of feuilletine crunch onto cake inside dam
23. Add ganache on top of feuilletine crunch (remaining within buttercream ring)
24. Add next cake round
25. Repeat steps 21-24, but placing third cake round upside down
26. Pipe buttercream liberally on top of third layer and spread across top and sides of cake then level using turntable
27. Refrigerate cake for an hour to firm outside layer
28. Meanwhile, crush remaining hazelnuts
29. Decorate cake with piped buttercream, Ferrero Rochers and crushed hazelnuts