Preheat your oven to 350°F or 177°C. Line a big baking sheet with parchment paper or a silicone baking mat.
Beat 4 egg whites (at room temperature) on medium-high with an electric mixer with a whisk attachment until they form soft peaks, around 5 minutes.
Dump in ½ cup of superfine sugar and mix it on medium-high for about 30 seconds. Repeat with the remaining ½ cup. Then, crank up the speed to high and keep beating for a couple of minutes. You’ll see glossy, stiff peaks form.
Fold in 1 teaspoon of vanilla extract, mixing for a full minute. Grab a silicone spatula and mix in 1 teaspoon of cornstarch and ½ teaspoon of cream of tartar.
Scoop the pavlova mixture into the prepared baking sheet and spread it into an 8-inch or 9-inch circle. You can actually play around with the shape now. Make a shallow dip in the middle for the toppings.
Pop the baking sheet in the preheated oven. Once you close the door, immediately dial the heat down to 200°F or 93°C. Bake it for around 90 minutes. If you see any brown spots, rotate the sheet for even baking.
Switch off the oven and let the cake cool inside for about 1 hour. When it completely cools, spread some lemon curd, pipe it with whipped cream, and top it with berries. Enjoy!