Preheat oven to 300 degrees F. Position the racks in the upper and lower thirds.

Cut a piece of parchment to fit a large baking sheet. Trace 4" circles, at least 2" apart on one side of the parchment (use a large a large biscuit cutter or canning lid jar - they might short of 4", but they'll serve great as a guide). Flip the paper over, penciled side down, on the baking sheet and set aside.

Thoroughly clean the bowl of a stand mixer. Rinse with a little vinegar and wipe dry.

Add the egg whites and salt to the bowl*, affix the whisk attachment, and start the mixer on medium-speed until the egg whites begin to turn a more opaque white, then increase speed to medium-high until soft/medium peaks are reached. Check by stopping the mixer and lifting the whisk attachment to inspect the peak on the whisk. It won't be stiff, but it won't drip, either. It takes just a couple of minutes).

Resume whipping at high speed and slowly add the sugar. (I usually add it by the heaping tablespoon; let it mix, then add the next.) Continue whipping until the meringue is very pillowy in the bowl. Stop the mixer, and remove the whisk. The egg whites should be very stiff, smooth, glossy, and pillowy, and hold a thin peak when the whisk is turned upside down. You can also test the bowl: remove the bowl from the mixer and turn it upside - the egg whites shouldn't budge.

Add the vinegar, corn starch, and vanilla to the meringue. Whisk on slow very briefly until combined (this happens fast). The meringue will be slightly looser and very glossy.

Use a large spoon to divide the meringue evenly among the 8 circles, piling the meringue tall in the center of each.

Use a small spoon or offset spatula to begin creating a crater in the meringue by dabbing it down in the center and pulling up to create a rim. I prefer some height to my mini pavlovas, so I don't fill the traced circle with meringue, rather, I use the tracing as a guide to keep my pavlovas round.

Gently smooth out any weird bumps or strands, keeping in mind that the pavlova will bake up exactly as it looks, bumps and all.

Place the baking sheet on the lower oven rack, and bake for 30 minutes undisturbed.

Turn off the stove, open the door for a few seconds to let the the most intense heat vent, close the door and let the pavlovas rest in the cooling oven for another 30 minutes. This is when the pavlovas will set up and form the crisp shell.

Increase heat to medium-low. Stir constantly to prevent the eggs from setting up. Keep stirring until the mixture thickens and begins to resemble a creamy jelly. This will take about 10 minutes. If you have an instant read thermometer, you're looking for the curd to reach 170°F. The curd should lift and then fall - not drip or drizzle - from the whisk or spatula.

Strain the curd through a fine mesh strainer over a bowl. (Use a spatula to push the mixture through the mesh.) Let the curd cool. (Accelerate the cooling process by placing the bowl in a larger bowl half-filled with ice water.)

Curd can be made ahead: refrigerate the curd for up to 2 weeks.

Just before serving, pour the heavy cream into the bowl of a stand mixer and, using the whisk attachment, whip at medium-high speed.

When the cream starts to thicken (the whisk will leave light tracks as it spins), add the sugar and vanilla (if using).

Continue whipping until the cream is pillowy and forms soft/medium peaks. Use immediately**.

Very gently, fill and spread the whipped in the pavlova's crater. Spoon a heaping teaspoon full of curd in the center, and use a knife to swirl the curd through the whipped cream. Repeat with the remaining pavlovas. Serve immediately.