Heat the oven to 200C/180C fan/gas 6 and line a 30cm traybake tin with baking parchment. Whisk the oil, eggs, soured cream and cooled coffee together in a large jug. Combine the flour, cocoa powder, bicarb, baking powder, both sugars and a pinch of salt in a large bowl, then whisk the wet ingredients into the dry until the mixture is smooth and no pockets of flour remain. Pour into the tin and bake for 20-22 mins, or until a skewer inserted into the middle comes out clean. Cool in the tin for 20 mins, then remove to a wire rack to cool completely.

Meanwhile, make the ganache. Warm the cream and malt powder, if using, in a small saucepan over a low heat, whisking until any powder has dissolved and the cream is steaming. Put both chocolates in a medium heatproof bowl and pour over the hot cream. Set aside for 1 min, then whisk until smooth and glossy. Leave to cool completely, then keep chilled until ready to use.

For the cherries, combine all the ingredients in a bowl, then spread over a baking tray lined with baking parchment. Roast for 20 mins, then leave to cool.

When ready to assemble, whip the ganache using an electric whisk for 3-4 mins until it holds stiff peaks and resembles buttercream. To make the kirsch cream, pour the cream, kirsch, vanilla seeds and icing sugar into a large bowl and whip to soft peaks. Put the cooled sponge on a serving tray, spread over the ganache, then spoon over the cream. Dot over the cherries and sprinkle over the hazelnuts. Will keep chilled for up to three days.