Preheat oven to 275F. Having the pavlova enter the oven at a higher temperature will help the crust to set and create the structure for the pavlova.
Wipe down the metal/glass bowl with a few drops of vinegar or lemon juice. This will help wipe off any grease that may be lingering on the bowl.
Separate 3 egg whites. Make sure eggs are room temp as they’re easier to whip and gain more volume. Start whipping on a low-medium speed (4 on a kitchen aid) until your eggs are broken up and begin to foam; once you reach a soft peak stage, you can increase the mixer one level (6 on a kitchen aid)
Begin adding the caster sugar (or grinded granulated sugar) one tablespoon at a time every 30-45 seconds. This should take a total of 10 minutes, Make sure you scrape down the sides of the bowl until all caster sugar is dissolved. Your peaks should be becoming stiffer by this point.
Bring back down to a low-medium speed (4 on a kitchen aid) and add the vinegar, cornstarch, and vanilla. Keep mixing on level 4 for another 5 minutes.
Your meringue should have reached stiff peaks. You should be able to comfortably turn your mixing bowl upside down with your meringue inside it - it should remain stable in the bowl and not fall out.
Scoop or pipe your meringue inside the traced 6-inch circle. Pile your pavlova to be around 10-15cm tall. Then create a small/medium smooth crater on the top of your pavlova, this will be a nest that can hold the cream and fruit you top your pavlova with.
Bring the oven temperature down to 200F and place your Pavola inside to bake for 1 hour and 10 minutes.
Once the pavlova has baked for an hour and 10 minutes, keep the oven door closed and leave the pavlova inside the oven for 1 1/2 hours minimum. You can also keep the pavlova inside the oven overnight.