1. Preheat the oven to 190°C/375°F/gas mark 5. Roughly chop the chocolate, set 20g aside for later, and put the remaining 180g into a heatproof bowl. Set the bowl over a pan of steaming water and leave to melt gently, stirring frequently. Don’t let the base of the bowl touch the water. When melted and smooth, remove the bowl from the pan and leave to cool until needed.
2. Meanwhile, beat the soft margarine with the icing sugar until very light, creamy and fluffy; you can do this with a wooden spoon or an electric whisk or mixer. Gradually add the eggs, beating well after each addition. Gradually beat in the flour. When the mixture is very smooth, gradually beat in the cooled, melted chocolate. When thoroughly combined, stir in the reserved chopped chocolate. Divide the mixture between the prepared tins and spread it out evenly. Bake for 8 minutes – the mixture will not be cooked but will have started to form a crust. While the mixture is baking, whisk the egg whites with the cream of tartar in a bowl until stiff peaks form. Whisk in the sugar in four batches, to make a smooth and glossy, thick meringue. Fold in the chopped hazelnuts.
3. Remove the cake tins from the oven and reduce the temperature to 170°C/325°F/gas mark 3. Divide the meringue equally between the two brownie-filled tins, and gently spread it over the still soft mixture to cover evenly. Smooth and flatten the surface of the meringue in one of the tins and ‘peak’ the meringue in the other using a skewer or the tip of a knife – this will be the top of the cake. Return the tins to the oven and bake for a further 25 minutes, until the meringue is firm to the touch. Remove from the oven and leave to cool before unmoulding.
4. To make the filling, whisk the cream until soft peaks form, then add the icing sugar and 200g of the raspberries. Whisk briefly, to make a thick, pink cream. Fold in the remaining 100g of raspberries. Run a round-bladed knife around the inside of each tin to loosen the cakes. Turn out the flat-topped meringue cake on to a serving plate, meringue-side down. Spread with the raspberry cream. Top with the second cake, with the peaked meringue side uppermost. Decorate with raspberries, hazelnuts and pistachios.
Recipe courtesy of Miranda Gore-Brown, Miranda Gore-Browne Beautiful Baking