Preheat oven to 150°C. Line a large baking tray with baking paper and sketch out a 20cm circle onto the paper.
Place the egg whites and salt in the largest bowl of an electric mixer and whisk until soft peaks form. Add ½ cup of sugar and beat for 1 minute before adding the next half cup and beating for another minute. Continue with the remaining sugar. When the last half cup of sugar has been added, continue to beat for 3 minutes. Remove the bowl from the mixer.
Combine the cornflour, vinegar and vanilla essence in a small bowl, stirring to remove any lumps. Stir carefully through the egg white mixture until just combined. Using a large spoon or spatula, spoon the mixture onto the tray, inside the drawn circle. Pile mixture on top of each spoonful and smooth to create the circular shape of a pavlova.
Place in the oven and immediately turn to down to 120°C. Bake for approx. 1-1¼ hours, or until the outside is a crisp shell and dry to touch. Turn off the oven, place a wooden spoon in the door so that it is slightly ajar and allow the pavlova to cool in the oven. It will most likely crack.
When completely cool, spread with whipped cream and decorate with fruit. Finish with the candied macadamias and serve immediately.