1. Preheat the oven to 300F (150C/gas 2/fan 130C). Line a heavy baking sheet with baking parchment and draw a 91⁄2in (24 cm) circle on it.
2. Put the egg whites into a very large, grease-free bowl or bowl of a stand mixer.
3. Mix the cornstarch and sugar together.
4. Using the stand mixer or electric beaters, whisk until soft peaks form. At this point start adding the sugar mixture, 1 tbsp at a time. Mix until thick and glossy, and stands up in firm peaks. Add the vinegar, and continue whisking until incorporated.
5. Spread the meringue over the circle, leaving a 1⁄2in (1 cm) border. Using the back of a large spoon, make a shallow dip in the middle for the filling, then build up the sides as high as you can, using a palette knife to make swirly peaks on top.
6. Bake the meringue case on the middle shelf for 20 minutes. Reduce to 275F (140C/gas 1/fan 120C) and bake for 40 minutes (1 hour in a gas oven). Turn off the oven but leave the meringue inside for 1-3 hours, with the door closed.

FOOL

1. Best to do this ahead or after the pavlova is cooled. Do not cook this while the pavlova is in the oven, resting (the heat can affect the cooling process in the oven.
2. Gently cook the gooseberries and 1/2 cup (100g/4oz) sugar, covered, over a low heat for 15 minutes, stirring once or twice. When they are soft, drain (discarding the juices) and leave to cool thoroughly.
3. To make the fool, whisk the brandy, lemon juice and 2 tbsp sugar in a large bowl for 1 minute. Pour in the elderflower cordial and cream and whisk until mixture forms soft peaks. Fold in the drained fruit .
4. Remove the meringue from the parchment, then put it on a large flat plate or cake stand. Pile in the fool filling and serve immediately.