Preheat oven to 130°c. Line a 30x40cm baking tray with baking paper.
Add egg whites and cream of tartar to the large clean bowl of a stand mixer. Beat on medium speed until soft peaks form. Gradually add sugar, 1 tablespoon at a time, and continue beating until stiff and glossy. Sprinkle over cornflour, vinegar and vanilla and gently fold through.
Add large dollops to tray and spread mixture across baking paper, leaving a 3cm border on paper. Drizzle over 2 tbs jam and lightly swirl through mixture.
Reduce oven to 100°c and place tray into oven. Bake for 30-45 minutes then turn off oven and leave pavlova to cool slowly and dry in oven for 2 hours or overnight.
Top pavlova with cream, fruit and mint, then drizzle over remaining jam and serve.