Preheat your Yoder Smokers pellet grill (or oven) to 300°F, set up for indirect cooking with the diffuser plate in place.
Prepare a half sheet pan lined with parchment or a silpat.
Make a slurry by combining the vanilla extract and cornstarch together in a small bowl. Set aside.
Using an electric mixer, begin making your meringue by whipping the egg whites with the cream of tartar on medium-high speed until you have about tripled in volume. You are looking for an even foam that is somewhere in between stiff and medium peak. Once you have reached this volume, begin gradually adding the sugar one tablespoon at a time over the highest speed on your mixer. Scrape the bowl if necessary and mix until thick and glossy and maintains a stiff peak.
Gently fold in your slurry into the meringue mixture, until barely combined (a little streaking is okay).
Place all the meringue in one large dollop onto the middle of your prepared sheet pan. Spread out the meringue using a spatula or the back of a spoon creating a large disc with a slight divot in the center to create a basket effect to place the toppings once the meringue is finished baking.
Bake the meringue for 1 hour at 300°F on the top shelf of the pellet grill. You can check it after 45-50 to ensure it is progressing well, and rotate the pan if needed.
After that hour, it should be slightly browned (very slightly), with a crispy exterior and soft interior. Set aside to cool while you prepare the toppings.
Macerate the strawberries by sprinkling a little sugar over them and letting them set. The sugar will extract the juices from the strawberries and soften their overall texture.
Whip heavy cream with powdered sugar until it reaches a medium-stiff peak.
Build your pavlova once it has cooled properly. First by placing the whipped cream into the center of the pavlova, then top with the macerated strawberries.