Preheat your oven to 110 deg C (225 F). Line a baking sheet with parchment paper and draw circles (to outline) using an espresso cup as your guide. (mine measured 6 cm or 2 ¼ inches). Turn the sheet over and set it aside.
Separate your egg whites over two bowls. (Freeze the egg yolks to use in another recipe). Next, add the egg whites to the bowl of your stand mixer.
Beat the egg whites on a low speed (no more than three on the dial) until soft peaks form. Slowly, add the sugar one tablespoon at a time. Ensure that the sugar is dissolved before adding the next tablespoon. (This can take anywhere between 10-15 minutes - have patience!).
Combine the vinegar and cornstarch to make a slurry and add it to the meringue. Raise your speed to number 5 or 6 and beat for another 45 seconds.
Place the pavlova meringue into a piping bag.
Pipe little circles on the corners of your baking tray. (This will prevent the parchment paper from slipping or moving).
Starting in the centre of your outlined circle, pipe the meringue to form the base. Then, to create the pavlova nests, pipe three layers on the circle's edge (this creates a "pocket" that we can fill up).
Bake in the oven for 45 minutes. Turn the oven off and allow the pavlova nests to cool in the oven before serving.