Preheat the oven to 150 °C.
Whisk the egg whites in a large bowl (with an electric whisk or stand mixer with whisk attachment) until soft peaks form.
Gradually add the castor sugar to the egg whites, small amounts at a time, whisking constantly until the mixture is stiff and glossy.
Add the vinegar or lemon juice, cornflour and vanilla and mix well.
Dot a large roasting tray with some of the mixture, then place a sheet of baking paper on top (so that it sticks like glue).
Pour the pavlova mixture onto the tray and shape with a spoon or spatula into a circle with a diameter of about 23 cm (draw a circle on the back of your baking paper, if necessary).
The mixture will rise a bit around the sides, so leave enough space. Place in the oven and immediately turn down the temperature to 120 °C.
Bake for 11⁄4 hours, then switch the oven off and leave to cool in the oven for about 21⁄2 hours without opening the oven door.
To serve: Carefully remove the baking paper from the bottom of the pavlova and transfer to a serving dish (it will have a few cracks, but that’s 100%).
Top with whipped cream and lemon curd, swirling the cream and curd together softly.
Top with lashings of passion fruit pulp and serve at once, sliced.
Pavlova must be assembled just before serving as it becomes soggy on standing.
Store the unassembled baked meringue on the baking tray covered with a sealed large plastic bag.
It can be baked a day ahead if stored in an airtight container.
Recipe extract from Cape Mediterranean by Ilse van der Merwe published by Penguin Random House. The book retails for 360