Step 1

Adjust the oven rack to the middle position and pre-heat the oven to 375ºF (190ºC). Grease two 6-inch/15cm round cake tins with vegan butter and line their bottoms with rounds of parchment/baking paper.

Step 2

Cream together the vegan butter, oil and sugar until pale and slightly fluffy. You can do this using a stand mixer fitted with the paddle attachment, a hand mixer fitted with the double beaters or by hand using a large balloon whisk.

Step 3

Add the dairy-free yoghurt and mix until well combined.

Step 4

Add the vanilla and hazelnut flavouring (optional), and mix to combine.

Step 5

In a separate bowl, sift together the gluten free flour blend, baking powder, xanthan gum and salt. Add the ground hazelnuts and whisk until evenly distributed.

Step 6

Beginning and ending with the dry ingredients, alternately add the dry ingredients (in three batches) and dairy-free milk (in two batches) to the butter-sugar mixture, mixing well after each addition, until you get a smooth cake batter with no flour clumps.Tip: This alternating way of adding dry and wet ingredients helps to maintain the emulsion of the butter in the cake batter, ensuring that your batter remains smooth and that the final baked cake has the perfect crumb. When alternating dry and wet ingredients, make sure to always end with the dry.

Step 7

Divide the batter evenly between the two prepared cake tins and smooth it out into even layers.

Step 8

Bake at 375ºF (190ºC) for about 25 minutes or until golden on top and an inserted toothpick comes out clean. After 20 minutes in the oven, cover the sponges with a sheet of aluminium foil, shiny side up.

Step 9

Allow the sponges to cool in the cake tins for about 10-15 minutes, then turn them out onto a wire rack to cool completely.Make sure that the sponges are 100% cooled to room temperature before you level them and start assembling the cake.

Step 10

Using a hand mixer fitted with the double beaters or a stand mixer fitted with the paddle attachment, cream the butter and powdered/icing sugar until pale and fluffy, for about 5 minutes.

Step 11

Sift in the cocoa powder and salt, and whip for a further 2-3 minutes, scraping the sides and bottom of the bowl occasionally, until fully combined.Tip: You can tailor the amount of salt to your personal preference – add it slowly (pinch by pinch), mixing well after each addition, and taste before adding more.

Step 12

Add the melted and cooled chocolate, and whip until fully combined.

Step 13

If the sponges are domed, level them using a sharp, serrated knife.

Step 14

Place the bottom sponge on a cake stand or serving plate of choice.

Step 15

Spread a generous layer of buttercream on top, but leave enough buttercream for the top and sides of the cake. Smooth it out into an even layer, using a small offset spatula.

Step 16

Place the other sponge on top, with the bottom of the sponge facing upwards (this will give you a nice flat top).

Step 17

Use most of the remaining buttercream to cover the top and sides of the cake, reserving some for piping decorations on top. Smooth out the top and sides with a cake scraper or a small offset spatula.

Step 18

Chill the frosted cake in the fridge for at least 30 minutes or until the buttercream is firm to the touch.

Step 19

Place the chopped dark chocolate into a heat-proof bowl.

Step 20

In a saucepan over medium-high heat, cook the vegan heavy/double cream alternative until it only just comes to a boil.

Step 21

Pour the hot cream over the chocolate and allow to sit for 2-3 minutes, then stir together until smooth and glossy.

Step 22

Allow the ganache to cool slightly at room temperature (or very briefly in the fridge) until it’s still pourable but not too runny.

Step 23

Transfer it to a squeeze bottle (you can also just use a spoon) and use it to create the chocolate ganache drip down the sides. Then, cover the top of the cake with the ganache and smooth it out using a small offset spatula or the back of a spoon. You can create swirls in the ganache for extra decoration.Tip: Alternatively, you can pour the ganache on top of the cake and then gently guide it to drip down the sides with an offset spatula or the back of a spoon.

Step 24

Chill the cake in the fridge for about 15-30 minutes or until the ganache has set and is no longer sticky/tacky to the touch.

Step 25

Transfer the remaining buttercream to a piping bag fitted with an open star nozzle.

Step 26

Pipe dollops of buttercream on top of the set ganache, and then sprinkle on the chopped toasted hazelnuts.

Step 27

Slice and serve.

Step 28

The gluten free vegan chocolate hazelnut cake keeps well in a closed air-tight container or wrapped in cling film in the fridge for 3-4 days.Before serving, take the cake out of the fridge and leave it at room temperature for at least 15-20 minutes. The chocolate buttercream frosting will be fairly firm directly out of the fridge, and leaving it at room temperature for a while softens it to its original luscious, velvety texture.