Preheat oven to 200 degrees F
Place a sheet of parchment paper on a sheet pan
In a medium bowl, sift together cocoa powder and cornstarch; set aside
Place the egg whites in a bowl of an electric mixer with whisk attachment
Beat egg whites on high speed until stiff peaks have formed
Slowly add in sugar and whisk until egg whites are shiny, about 2 minutes
Remove the bowl from the mixer and gently fold in sifted cocoa powder, cornstarch and vinegar until combined
Divide the meringue into two for two 6 inch pavlovas or spread all the merinue into one to create a 9 inch pavlova; pile the meringue onto the parchment paper and smooth it to form a circle
Bake meringue for 1 1/2 hours and then turn off oven and allow the meringue to cool completely in the oven
Place the meringue on a serving dish and spread whipped cream in the center
Arrange the raspberries over the whipped cream and garnish with chocolate shavings and powdered sugar

Sweet Whipped Cream
In a large bowl of an electric mixer with whisk attachment whisk the whipped cream until it starts to thicken
Slowly add the sugar and vanilla extract and continue beating until firm
Use immediately!