Preheat the oven to 150oc. Line a baking tray with parchment.
Whisk the egg whites until they start to form soft peaks then begin to add in the caster sugar. Slowly add in the sugar in batches until the meringue is smooth and glossy.
Add in the vanilla extract, white wine vinegar and cornflour and whisk until you have stiff peaks.
Pipe the meringue onto the baking parchment in the shape of a heart making the sides higher than the centre. You may want to draw the shape onto the parchment before you start to pipe.
Place in the oven for one hour then turn off the oven and leave to cool completely in the oven before removing.
Once cooled, whip the cream with one tablespoon icing sugar until forming soft peaks.
Mix 150g strawberries and 100g raspberries with the remaining icing sugar then blitz in a blender until smooth. If you want to remove any seeds and have a really smooth sauce then pass through a sieve.
Fill the meringue with the fruit, top with the cream and drizzle the sauce over the top.