* 200g ready-to-eat, stoneless prunes
* 6 tbsp Armagnac or brandy
* 300g good-quality dark chocolate (minimum 55% cocoa solids but no more than 70%)
* 140g unsalted butter
* 5 large eggs, separated
* 140g golden caster (superfine) sugar
* 300g mixed berries (blackberries, raspberries and strawberries), to serve
* icing sugar, for dusting
1. You’ll need to soak the prunes preferably overnight in Armagnac. Before soaking, place the prunes in a pan along with 275ml of water or until they are completely covered. Bring them to a simmering point and simmer for 20–30 minutes.
2. Pour the prunes and their cooking liquor into a bowl and stir in four tablespoons of the Armagnac while they are still warm. Leave to cool. Once cool, cover the bowl with clingfilm and chill overnight (or for a few hours if you forget to start a day earlier).
3. When you are ready to make the cake, preheat the oven to 170C (325F/gas mark 3) and grease and line a 23cm (9in) springform cake tin with baking parchment. Start by breaking the dark chocolate into small pieces into a bowl, add the butter and melt them over a bain-marie or an ovenproof bowl set over a pan of simmering water; it will only take a few minutes.
4. Place two to four sheets of kitchen paper in the water to stop the bowl having direct contact with the heat and burning the chocolate. Stir until you have a smooth, glossy mixture. Off the heat, add the remaining Armagnac, mix well and leave to cool.
5. Meanwhile, in a large bowl and using an electric hand whisk, whisk the yolks and sugar for a few minutes until the mixture has partially whitened and once the whisk is lifted it leaves a ribbon-like trail, what’s known as ribbon stage.
6. Cut the soaked prunes in half and add to the melted chocolate (this will help to reduce the temperature of the chocolate), and then mix the chocolate and prunes into the whisked egg yolk and sugar mixture.
7. In another large bowl, whisk the egg whites to soft peaks (use the electric hand whisk but ensure that it is clean and with no trace of water or yolks or your egg whites will not form soft peaks). Then, fold it into the egg and chocolate mixture.
8. Spoon the cake mixture into the prepared tin and bake it in the centre of the preheated oven for 25–30 minutes or until the centre feels springy to the touch. Allow the cake to cool in the tin; it will deflate quite a bit so don’t be alarmed. When it is completely cool, cover the tin in clingfilm and chill for several hours.
9. Take the cake out of the fridge a couple of hours before serving. Decorate the cake with the berries placing them on top in a haphazard but attractive sort of way. Cut most of the strawberries in half lengthways but keep the green stems, they will go further this way and look prettier too. Make sure the fruit is dry otherwise the icing sugar will melt and you will not get a lightly dusted coating.
10. Just before serving, dust the top with icing sugar. Cut the cake into small slices (it is rich) and serve.
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