Method

• 1.
  Preheat the oven to 200°C. Line the bottom of 2 x 20cm springform cake pans with baking paper and grease the sides. Alternatively, grease the bottoms and sides of 2 x 20cm regular cake pans, line with baking paper, and grease the baking paper.
• 2.
  In a large bowl, whisk cocoa, flour, baking powder, bicarb soda, salt and sugars. In a separate large bowl, add sunflower oil, eggs and kefir and whisk just to combine. Add to dry mixture, using a spatula to gently fold through. Add 220g hot coffee and mix gently to combine. It will look runny at first, but will soon come together into a glossy, pourable batter.
• 3.
  Divide batter evenly between the two cake pans, about 600g per pan. Bake for 30 minutes or until a skewer inserted into the middle comes out clean. Set aside to cool for about 30 minutes, then slide a butter knife along the sides to help release the cake. Brush the tops lightly with the remaining 1 tbs extra coffee (discard any extra coffee).
• 4.
  Invert one cake onto a board, remove the baking paper, then invert it again (domed side up) onto a cake stand or the platter you intend to serve it on. Invert the other cake onto a board (don’t remove the paper). Invert it again, onto a plate, so that it’s paper-side down. (This will help prevent it from sticking.) Set both cakes aside to cool completely.
• 5.
  Make the praline: with the oven still at 200°C, spread the hazelnuts onto a baking paper-lined medium baking tray and bake for 8 to 10 minutes, or until deeply golden, shaking the pan halfway through baking. Set aside, keeping the tray and baking paper. You’ll use them again later.
• 6.
  Place a large saucepan over a medium high heat and, once quite hot, sprinkle in 1/3 of the caster sugar to cover the base. It should immediately start to melt at the sides but not brown too quickly. Swirl the sugar in the pan a little, then add another 1/3 of the sugar, allowing it to melt a little before adding the remaining 1/3. Turn the heat down to medium and cook until the sugar is an amber caramel, stirring with a spatula just a couple times (but not much more). Add the hazelnuts and 1/4 tsp salt, stirring to coat, then quickly transfer the mixture to your baking paper-lined tray and leave to cool completely.
• 7.
  Once cool, roughly break apart the praline and add it to a food processor. Pulse a few times until you have very coarse crumbs, then measure out about 1/2 cup (75g) of the mixture and transfer to a bowl. Blitz the remaining mixture in the food processor for about 5 minutes or until it turns into the consistency of a smooth nut butter, stopping to scrape the inside of the bowl with a spatula as necessary. Transfer this to a separate bowl.
• 8.
  Make the mascarpone cream: add all the ingredients to a stand mixer and beat on medium-high speed for 1 1/2 to 2 minutes, or until you have medium peaks. Refrigerate if not assembling right away (you want it nice and cold).
• 9.
  When ready to assemble, top the cake on your cake stand with half the cream mixture. Spoon over about 2 tbs of the smooth praline and gently swirl it through the cream with your spatula. Top with another 2 tbs of the praline, this time without swirling. Sprinkle with half the praline crumble. Carefully invert the other cake on top now, removing the paper. Top with the remaining cream and repeat the same process with the smooth praline and praline crumble. Serve right away, or refrigerate overnight to firm up the cream before serving.