To make the mini pavlovas
Preheat the oven to 275 degrees with a rack placed in the lower third of the oven. Prepare a baking sheet with parchment paper. Use a pencil to draw 5-inch circles onto the parchment. Flip the parchment over.
Clean out your mixing bowl and beaters carefully with some vinegar. Any residual oil left in the bowl can prevent the meringue from properly coming together.
Mix the vanilla and white vinegar in a bowl. Mix the sugar and cornstarch together in a separate bowl. Using an electric mixer, beat the egg whites and cream of tartar in a large bowl until soft peaks form. Begin at a low speed and gradually increase the speed to medium. Once soft peaks have formed, add the sugar, 1 tablespoon at a time, beating constantly until thick and glossy. While doing this gradually increase the speed so that the mixer is at the maximum speed once all of the sugar has been added.
Continue whipping until the mixture holds stiff peaks. You should be able to turn the whisk upside down and have the peaks hold proudly. Stop the mixture, add the vinegar and vanilla. Beat for a few more seconds to fold in the vanilla and vinegar.
Using a large spoon, divide the meringue mixture among the four circles. Gently make smooth swirl patterns with sweeping strokes. Make sure the tops of the pavlova are mostly flat and make a slight indent in the middle for where the whipped cream and pear will sit. Work quickly and make sure to be gentle so as not to remove any of the air that was painstakingly whipped into the meringue.
Put the meringue in the oven and immediately turn down the heat to 250°F. Bake for 50-60 minutes. The pavlovas are done when the outsides are dry to the touch, are very slightly browned, and sound hollow when tapped. Small cracks may form.
Turn the oven off, but leave the pavlova inside with the oven door ajar. Let sit until the pavlova is completely cooled, or overnight.
To make the poached pears
Flatten the bottoms of the pears by shaving a bit off. This will help them sit on the pavlovas. Use a melon baller to core out the seeds from the bottom of the pear.
In a medium saucepan, combine all of the ingredients except for the pears. Cook over medium heat, making sure to stir, until the sugar dissolves and the mixture comes to a boil. Add the pears. The liquid should fully cover the pears. Reduce the heat and simmer until the pears are tender, about 20 minutes. Remove the pears from the pot and continue to boil the liquid in the pan. Reduce by half, about 25-30 minutes.
To make the whipped cream
Make sure to start with cold cream. Using an electric mixer, or by hand, beat the heavy cream in a medium-sized bowl until soft peaks form. Gradually add in the sugar and vanilla; continue to beat until you reach stiff peaks. Do not over-beat.
To serve
Carefully place the pavlovas onto plates. Spoon whipped cream into the slot that was made before baking. Place a pear on top and drizzle over with the poaching liquid. You can also choose to cut the pear in half for serving.
