Start by making the pavlova shell. Whisk the egg whites till stiff then gradually add in the sugar in spoonfuls beating constantly.fold in the vanilla and cornflour. Mix the cocoa with a little hot water then add to the meringue and fold in unevenly. Spread the meringue onto a baking tray lined with non-stick paper, form into a mound and make a slight dip in the middle. Bake in the oven at 130°C for 1 ½ hours. Meanwhile, make the caramel sauce by boiling the sugar and water together until golden. Stir in the cream, be careful it may bubble. Remove off the heat and stir in the butter and salt and put aside. For the filling, whip the cream and vanilla till stiff and whisk in the mascarpone. Place the cake cubes into the base of the meringue and pour over the bourbon or brandy. Spoon over the cream filling and decorate the top with berries and leaves. Pour over the salted caramel sauce before serving.