Hazelnut chocolate dacquoise

Put the chocolate into a large bowl and set aside. Put the egg yolks and sugar into another large bowl and mix with a balloon whisk until just combined. Try not to introduce too much air. Pour the milk and cream into a medium heavy-based pan and bring to the boil. Add 2 tbsp of the hot liquid to the egg yolks and mix well. Slowly pour the remaining milk mixture into the egg yolks, stirring constantly with a spatula. Return the mixture to a clean pan and stir over a low heat for 5-6 minutes, until it coats the back of a wooden spoon. Take care not to let it boil.

Strain the mixture through a fine sieve, then pour a third of it into the chocolate. Working from the centre outwards, stir with a spatula to make a smooth emulsion. Add the remaining mixture in two batches, stirring until smooth and shiny. Whizz the mixture with an electric hand blender to ensure it’s smooth. Cover with clingfilm and chill for at least 6–8 hours or, preferably, overnight.

To make the compote, put the gelatine in a small bowl, add the water and set aside to soak. Gelatine allows the compote to set so it won’t seep into the meringue sponge. Put the thawed berries into a medium pan with the mashed and strained raspberries, lemon zest and juice and the invert sugar. Place over a medium heat and cook gently and briefly to warm the mixture through.

Combine the caster sugar and pectin in a bowl, then stir into the fruit and bring to the boil. Take the pan off the heat and stir in the gelatine until it has dissolved completely. Transfer the mixture to a medium bowl. Allow to cool, then cover and chill for about 4 hours, or overnight, until firm.

The key to a great dacquoise is air. The egg whites and sugar are whisked until light and the dry ingredients are sifted to incorporate even more air. Use a light, careful touch when folding the two together, so you don’t beat out all the volume.

Whisk 50g sugar with the egg whites until the mixture stands in soft peaks. Sift the flour and ground hazelnuts into a separate medium bowl, adding any bits left over in the sieve at the end, then stir in the remaining 100g sugar. Using a large metal spoon, gradually fold this into the meringue mixture until combined, taking care not to knock out too much of the air.

Spoon the mixture into a piping bag fitted with a 1cm nozzle. Pipe in spirals, working from the centre outwards, to fill two 20cm cake tins lined with parchment. Sprinkle each with half the chopped hazelnuts, then dust with icing sugar. Bake for about 20 minutes, until firm. Loosen the edges from the tin to remove. Cool on a wire rack, then peel off the parchment.

To assemble the dacquoise, put one of the sponges onto a serving plate. Take the other sponge and use a 5cm cutter to cut a circle out of the middle. Spoon the crémeux into a piping bag fitted with the 2cm star nozzle. Pipe a large rosette of crémeux onto the centre of the base layer and circle it with a border of large rosettes.

Spoon the berry compote into the second piping bag and snip about 4cm from the end. Carefully pipe the compote in between the piped crémeux border and the central rosette to fill any gaps. Place the second dacquoise on top and fill the hole with mixed berries. Dust lightly with icing sugar and serve.

Bake Off: Crème de la Crème (Hodder & Stoughton £25) is published on March 24. Buy it for £21.50, inc p&p, from The Sunday Times Bookshop