A spectacular cake with layers of chestnut and coffee mousses sandwiched with almond meringue, topped with hazelnut meringues, chocolate shards and praline.
Equipment and preparation: You will need a 20cm/8in wide ring mould, at least 8cm deep, a chocolate transfer sheet (or plain acetate sheet) and a chef’s blowtorch.
For the chestnut mousse, heat the chestnut purée and four tablespoons of water in a pan and bring to a simmer. Drain the gelatine leaves and squeeze out any excess water, then stir into the chestnut mixture until dissolved.
Remove from the heat and strain the chestnut mixture through a sieve into a bowl. Leave to cool to room temperature then mix in the dark rum.
In a separate bowl, whip the cream until it forms soft peaks when the whisk is removed. Fold the whipped cream into the chestnut mixture. Cover and place in the fridge to set for at least two hours.
For the coffee mousseline, place the eggs, egg yolks and 70g/2½oz of the sugar in a bowl and whisk until pale and fluffy. (The mixture should leave a ribbon trail when the whisk is removed.) Sift in the flour and mix well.
Place the milk and remaining sugar in a large saucepan and bring to the boil. Slowly pour a third of the hot milk onto the egg mixture, whisking all the time. Then add the rest of the milk. Pour the mixture back into the pan and cook over a low heat stirring continuously. Simmer for two minutes or until thickened.
Remove the pan from the heat, and strain the custard through a fine sieve into a clean bowl. Stir in the softened gelatine and beat in one-third of the butter. Allow to cool, stirring occasionally to stop a skin forming. Beat the remaining butter with a handheld mixer at low speed for about three minutes until pale and fluffy. Increase mixing speed to medium and add the cooled custard a little at a time. Beat for five minutes until light and creamy. Mix the coffee powder with a teaspoon of water to make a paste. Stir the coffee paste and coffee liqueur into the custard mix. Set aside, covered, in the fridge.
Preheat oven to 150C/300F/Gas 2.
For the meringue layers, trace four circles around the cake ring onto baking parchment with a pencil.
Beat the egg whites with the cream of tartar until soft peaks form when the whisk is removed. Then slowly whisk in the caster sugar and whisk until stiff peaks form when the whisk is removed.
Blend the almonds with the icing sugar in a food processor for a minute. Fold the ground almond mixture and the flour into the whisked egg whites with a metal spoon until incorporated.
Transfer the meringue to a piping bag, fitted with a 1cm/½in plain nozzle. Pipe in a spiral onto the baking parchment circles starting from the centre and piping outwards. Sprinkle with the chopped hazelnuts and bake for an hour until dry and crisp. Remove from the oven and set aside.
Reduce the oven to 120C/250F/Gas ½. Line a baking tray with baking parchment.
For the brown sugar and hazelnut meringue, whisk the egg whites with the cream of tartar until soft peaks form when the whisk is removed. Add the sugar gradually, whisking well between additions. Whisk for another three minutes until stiff peaks form when the whisk is removed. Fold in three-quarters of the chopped hazelnuts and the cornflour. Transfer the meringue to a piping bag fitted with a plain nozzle. Pipe the meringue into small rounds and sprinkle the tops with the remaining hazelnuts. Bake for 25 minutes until crisp. Set aside to cool.
Meanwhile for the chestnut glaze, heat the sugar with 50ml/2fl oz water over a medium heat, stirring constantly, until dissolved. Then bring to a boil. Remove from the heat and stir in the drained, softened gelatine. Stir in the chestnut purée until thoroughly combined, then strain through a fine sieve. Set aside to cool.
For the chocolate decorations, melt three-quarters of the chocolate in a bowl set over a pan of simmering water. Melt the chocolate to 45C/113F (use a thermometer to measure this). Remove the bowl from the heat and add the remaining chocolate in small amounts, stirring as it cools and thickens. When the chocolate temperature reaches 31C/88F , using a palette knife, spread it over an acetate sheet or a chocolate transfer sheet, to a thickness of a 50p piece. Set aside to cool.
After a few minutes when the chocolate begins to set, score triangles into the chocolate at least 15cm/6in long. Leave to cool fully and firm up. Turn the oven up to 200C/400F/Gas 6. Line a baking tray with non-stick parchment.
For the praline, roast the hazelnuts and almonds on a non-stick baking tray for 8-10 minutes until golden-brown. In a saucepan, heat the sugar over a medium heat until it melts and turns to amber caramel – about 15 minutes.
Stir in the roasted nuts, then pour the mixture onto the lined baking tray and leave to cool. When completely cool break up the praline and blend in a food processor to a fine crumble. Set aside.
For the chocolate mousse, place the chopped chocolate into a large bowl. In a small pan slowly bring the milk to the boil. Meanwhile whisk the egg yolks and sugar together by hand until the mixture is pale and fluffy. Pour half of the boiled milk onto the egg mixture stirring all the time, then pour this back into the pan with the remaining milk, still stirring continuously. Cook over a low heat, stirring constantly, until the mixture has thickened.
Remove from the heat and strain through a fine sieve onto the chopped chocolate. Set aside to cool.
Whip the cream until soft peaks form when the whisk is removed then carefully fold it into the chocolate custard. Add the hazelnut liqueur.
To assemble the dacquoise, place the ring mould onto the presentation plate, to use as a guide. Place one circle of meringue into the cake ring and cover with a 2cm/in layer of chocolate mousse. Reserve any leftover mousse for patching up when the ring is removed. Place a second meringue layer on the top and chill in the fridge for 20 minutes. Remove from the fridge and spread over a 2cm/1in layer of coffee mousseline cream onto the meringue to a similar depth, cover with a third meringue layer and chill again for 20 minutes. Remove from the fridge and spread over a 2cm/1in layer of chestnut mousse. Top with the final meringue layer, but inverted so the surface is flat. Reserve any leftover mousse to smooth out any imperfections when the ring is removed.
If the chestnut glaze has set, warm it gently in a saucepan to a pouring consistency. Spoon the chestnut glaze over the top to just cover and then chill in the fridge until just before serving. To release the ring mould, run a lighted blowtorch around the outside of the mould. Gently ease the ring mould off, patch any holes and chill again. Decorate with the chocolate triangles around the sides, brown sugar and hazelnut meringues piled in the centre and chocolate curls and praline around the edges.
