Using a pencil and a large plate, trace a circle approximately 24cm in diameter in the centre of the paper. Use a smaller plate to draw a smaller circle in the middle of the large circle.
Preheat oven to 120ºC (100°C fan forced) and line a greased, flat oven tray with the marked-up baking paper.
Using an electric mixer (or stand mixer), add egg whites to a bowl and beat until soft peaks form. Gradually add sugar 1 tablespoon at a time, beating well after each addition until mixture is thick, glossy and sugar has dissolved.
Add corn flour and vinegar and beat until just combined.
Using the pencil marks as a guide, spoon meringue mixture onto baking tray, in the shape of a wreath.
Place in oven and bake for 1½ hours. Once finished, turn oven off and leave the door slightly ajar. Keep pavlova in the oven until completely cooled, before removing.
Whilst pavlova is cooling, heat a grill pan on medium heat. Slice peaches in halves and remove stones. Slice each half and grill peaches until just soft then set aside.
Roughly cut most of the chocolate from the outside of the honeycomb, setting aside or storing for later use, then cut honeycomb into chunks and set aside.
Whip cream and sugar, using an electric mixer until soft peaks form and spoon over pavlova wreath.
Decorate with grilled peaches, honeycomb and pistachios.