Preparation: 20 minutes, plus cooling
Cooking: 50 minutes
Makes: 4 sandwiched meringues
4 medium egg whites
120g caster sugar
110g icing sugar
1/2 tsp vanilla extract
1 tsp cornflour
1 tsp white wine vinegar
200g dark chocolate, melted
150ml double cream
1. Heat the oven to 140℃/275℉/gas 1 (120℃ for fan ovens). Lightly oil a baking sheet, line with baking paper and lightly oil this too.
2. Beat together the egg whites and caster sugar until very stiff. Add the icing sugar, vanilla extract, cornflour and vinegar, and beat for another 4 minutes until very stiff and glossy.
3. Pour 3 top melted chocolate over the meringue mix, stirring it through once only. Spoon the mixture into a piping bag fitted with a fluted nozzle – or a plastic bag with the corner snipped off – and pipe 8 swirled blobs onto the baking sheet.
4. Bake on a middle shelf in the oven for 35 minutes. Turn off the oven, open the door and leave the meringues inside to cool for about 30 minutes.
5. Reheat the leftover chocolate until smooth and runny. Remove from the heat, stir in the double cream and leave to cool until it’s spreadable. Use to sandwich together the meringues.