Preheat your oven to 350°F.
Whip the egg whites with a small pinch of salt until they’re white and foamy. If you’re using vanilla beans, add them in now, that way they can get evenly dispersed throughout the meringue.
Slowly add in the sugar, 1/4 cup at a time and keep whipping until you see that the meringue is super shiny and it’s forming stiff peaks. Ok, you’re done with the mixer for now.
Next, sift over the cornstarch, add the vinegar and if you’re using vanilla extract add it in now. Fold everything so it’s combined, and be gentle, you don’t want to deflate those beautiful egg whites you created!
Line a baking sheet with parchment paper. I put a tiny dab of the meringue under the corners of the parchment so it sticks to the baking tray and doesn’t slide all around while I mound the meringue on top and form it into a circle. You’re aiming for a diameter of around 8” here, but it doesn’t need to be perfect, and I think it looks better when it’s not perfect. You can trace a circle on the underside of the parchment paper if you prefer to have a bit of a guide for your meringue sculpture. Just make sure its on the underside of the paper, the pencil or pen will transfer to the meringue as it cooks. No good.
Then, place that meringue in the oven right away and lower the temp to 300°F as soon as you close the door. Let the pav bake for 1 hour, keeping the door closed, turn the oven off and let the pavlova cool in the oven. This can take a while, especially if your oven is very well insulated. I left mine in there for about 5 hours, the oven was still slightly warm, but 5 hours did the trick. The warmer temp at the beginning helps to give the pavlova the crispy outside and the long, low cooking and cooling is what will give you that soft marshmallowy center. It takes a while, but I promise it will be worth it.
Once your pav is finished baking, go ahead and whip up some heavy cream, make sure it’s very cold before you start whipping. Then mound in on top of the pav and top with your fruit of choice. This most likely will get eaten up right away which is a good thing since it really isn’t a dessert that keeps well. Enjoy!