Preheat oven to 200oC. Draw a 24cm (diameter) circle on a sheet of baking paper. Place, pencil-side down, on a baking tray. Dust lightly with 1 teaspoon cornflour
Using an electric mixer, beat eggwhites and cream of tartar in a large bowl until soft peaks form. Add sugar, 1 tablespoon at a time, beating constantly until thick and glossy. Add remaining 3 teaspoons cornflour with the last tablespoon of sugar. Fold through vanilla and vinegar.
Spoon meringue onto baking paper. Shape into a circle, using the pencil mark as a guide. Reduce oven to 100oC. Bake for 1 1/4 to 1 1/2 hours or until dry and crisp. Turn off oven and open oven door. Cool completely in oven (pavlova may sink during cooling).
Crumble meringue into dessert glasses. Layer with cream and raspberries. Sprinkle with mint leaves and serve immediately.