Preheat oven to 120C. Line an oven tray with baking paper.
Beat egg whites to soft peaks then continue beating and slowly add the Natvia baking sweetener a little at a time. Beat until the meringue has firm glossy peaks and Natvia is fully dissolved.
Drizzle over the vanilla and vinegar and sift over the cornflour. Fold through gently using a large metal spoon.
Scoop meringue into 4 portions on the lined tray and form into pavlova nests with the back of the spoon.
Place tray in oven and reduce heat to 100C. Bake for approximately 40 minutes until the meringue begins to firm and slightly brown. Turn off the oven and prop open the door to allow meringues to cool completely in the oven, this can take an hour or more.
Pavlova nests can be served immediately or store in an airtight container, ensuring they are completely dry in the pantry for 2-3 weeks (they must be kept cool and dry to store well).
When ready to serve combine half the passionfruit pulp with the yoghurt and spoon into pavlovas.
Top with raspberries and remaining passionfruit pulp. One pavlova with yoghurt and fruit is one serve.