Pre-heat oven to 150C/300F/Gas 2 and line two large, rimmed baking sheets with parchment paper or Silpat™ baking sheets. Set aside.
Using a stand or hand mixer, beat the egg whites until they thicken and turn white.
While still mixing, slowly add the sugar, one or two tablespoons at a time, until each addition is thoroughly incorporated into the egg whites.
Add the cream of tartar and corn starch and continue beating until the mixture is stiff and glossy.
Spoon the mixture onto the prepared baking sheets in equal-sized portions, as shown, using the back of the spoon to create an indent to place toppings after baking. If you want to get fancy you could pipe the meringue using a pastry bag with a piping tip.
Place the baking sheets into the preheated oven for 10 minutes, then reduce heat to 105C/225/Gas½. Continue baking for 45 minutes, then turn off the oven. Allow the pavlovas to rest in the oven for one hour without opening the door.
After one hour, remove from the oven. They can be served immediately from the oven, or stored covered in the refrigerator for a couple of days.
To serve, top with whipped cream (the whipped cream will soften and break through the crispy meringue exterior, so top them when ready to serve.
Then add your choice of fresh berries, mini-chocolate chips, and/or fresh herbs to garnish, if desired. Serve immediately after topping. Enjoy!
Notes
Eggs are easier to separate while they are still chilled. Once separated, reserve the yolks in the refrigerator for another use, if desired, and allow the whites to come to room temperature for 30 minutes prior to beating.