Place sugar and instant coffee in a mixer and blend until you obtain a smooth powder.
Beat the egg whites until you obtain a very firm meringue.
Gently incorporate (mixing slowly with a bottom-up motion) first the sugar and coffee mix and then also the sifted cornflour and vinegar.
Draw the outline of a flat plate on a sheet of baking paper, then turn the sheet (so that the drawing is facing downwards) and place it on the baking tray: the drawing should still be visible from the top side.
Using a spatula, transfer the coffee meringue onto the baking paper in the center of the circle, then level it to create a disc that remains within the confines of the circle and is flat on the surface.
Cook for about 1 hour in a fan oven preheated to 150°C, then turn off the oven and leave to cool completely, with the door closed.
When the base is now cold, transfer it to a serving plate.
Just before serving, whip the cold cream from the fridge together with the icing sugar.
Spread the cream in the center of the meringue, leaving the edges free, then decorate with cocoa and chocolate curls.
The cappuccino pavlova is ready, serve it immediately.
