Blackberry and hazelnut meringue ice cream sundaes

Method

1. To make the hazelnut meringues, preheat the oven to 200°C/fan 180°C/gas 6. Spread the hazelnuts over a baking tray and roast for about 8 minutes until lightly golden. Remove from the oven and set aside to cool, then finely chop.
2. Lower the oven temperature to 110°C/fan90°C/gas ¼. Line a large, heavy-duty baking sheet with baking paper. In a large glass mixing bowl, use an electric hand mixer to whisk the egg whites into stiff peaks. Gradually add the caster sugar, a spoonful at a time, and whisk to form a stiff and shiny meringue. Sift over the icing sugar, one third at a time, then gently fold into the meringue. Gently fold in the toasted chopped hazelnuts.
3. Drop 6 large spoonfuls of the meringue, spaced well apart, onto the lined baking tray. Bake for 2 hours until the meringues are crisp and sound hollow when tapped on the bases. Turn off the oven, then leave the meringues inside until completely cool.
4. Put half the blackberries into a mini food processor with the crème de mûre (see tip), then blend together until you have a smooth sauce. This can be made a few hours in advance and chilled in the fridge until needed.
5. Shortly before you’re ready to assemble and serve the sundaes, remove the vanilla ice cream from the freezer to soften, either in the fridge for 20-30 minutes or at room temperature for about 10-15 minutes. Meanwhile, in a medium bowl, whip the double cream until it forms stable (not too stiff) peaks. Crush 3 of the hazelnut meringues into small pieces and fold them in.
6. Layer spoonfuls of the blackberry sauce, vanilla ice cream, hazelnut meringue cream and the remaining blackberries in tall sundae glasses. Finish with another drizzle of the sauce and a few blackberries. Serve straightaway.