Preheat the oven to 225 degrees F. Place one rack in the upper-middle and one in the lower-middle position of the oven. Line 2 baking sheets with parchment paper.
In a small bowl, whisk together sugar, cornstarch, and salt. In the bowl of a stand mixer (or a large bowl if using hand mixer), combine egg whites, vanilla extract, and cream of tartar. Use the whisk attachment for the stand mixer.
With the mixture set on medium-low setting, whip the mixture until foamy, about 1 minute. While continuing to whip, gradually add the sugar mixture.
Turn the mixer to medium speed. Continue to whip the egg whites until they hold stiff peaks, 4 to 5 minutes. This may take less or more time depending on the humidity. Make sure that stiff peaks do form, but do not overwhip or they will become dry.
Gently fold in three-quarters of the crushed candy canes.
Using a spoon or a pastry bag fitted with a plain tip, form meringues on the prepared baking sheets. They should have a little peak, resembling the shape of Hershey’s kisses, and should each be about 1 ¼-inches wide.
Using your finger, gently poke 1 chocolate chip into the middle of each meringue. Gently patch the hole with meringue. Sprinkle the remaining crushed candy canes on top of the meringues.
Place the baking sheets in the oven and bake for 1 ¼ hours, switching the placement of the baking sheets and from front to back halfway through baking.
Turn off the oven and let the meringues rest in the oven until dry, about 1 ¼ hours (more time may be necessary in humid weather).
Remove the meringues from the oven and let cool for about 10 minutes. Serve.
Make sure the meringues are completely cooled before storing in an airtight container.