Preheat the oven to 200 degrees F.

Line a baking sheet with parchment paper.

In the bowl of a standing mixer, using the whisk attachment, beat the egg whites until thick and frothy, about 2 to 3 minutes. With the machine on medium-high speed, gradually add the sugar 2 tablespoons at a time. Add the vanilla, cream of tartar and the sea salt. Increase the speed to high and continue to whisk the egg whites until they hold a stiff peak, about 4 minutes longer.

Spoon 6 large dollops of the mixture onto a baking sheet, about 1 inch apart. Using the back of a spoon, smooth out the sides and make a shallow well in the middle of each meringue. Bake for 2 hours. The meringues should be crisp on the outside and have a chewy texture on the inside.

Meanwhile, make the passion fruit curd:  Combine the egg yolks with the remaining 1/2 cup of sugar, the passion fruit puree and the lemon juice in a medium size sauce pan and mix well. Place the saucepan over medium heat and cook, constantly stirring until the mixture becomes thick and coats the back of a spoon, 8 to 10 minutes.

Prepare an ice water bath. Place a clean, heat-proof bowl in the ice bath and strain the curd through a fine mesh sieve into the bowl. Discard any solids. Place a piece of plastic wrap directly on top of the curd and refrigerate until firm. The curd can be made up to 1 week in advance and stored in a resealable container in the refrigerator.

Cut the passion fruit in half and scoop the fruit into a bowl.

Assemble the pavlovas by spooning a dollop of the passion fruit curd into the well of each meringue. Spoon the fresh passion fruit over the top of each and serve immediately.