Preheat fan assisted oven to 130 degrees and lay parchment paper on oiled tray (or use meringue mix in corners to stick sheet to tray).
Mix egg whites at high speed until foamy and cloudy. Then add 1 tbsp caster sugar at a time until soft peaks form and all sugar dissolved. When whisking the sugar in, turn down to medium initially so you don't get soft peaks before all sugar has dissolved.
Lower speed and then mix cornflour and vinegar and add. Also add vanilla essence and whisk all through the meringue mix.
Spread meringue mixture onto greaseproof paper and form whatever shape you like but ensure middle not higher than outsides. You can leave it like that or smooth off the sides and lift ridges on all edges with back of knife. Alternatively you can fill the baking tray. Put meringue in oven for 30 minutes then turn down to 90 degrees for 90 minutes. Turn oven off and allow to cool in oven for 1-2 hours. Take out and allow to cool for further 1 hour before removing from baking tray.
Lightly whisk cream and add sugar if required and spread on top of pavlova, spread the Strawberries and crumble Cadburys Flake over the top.
