Weigh everything first and have all the ingredients ready to go. Have a baking tray lined with parchment paper, and a container to hold the piping bag ready. Set the oven temperature to 100°C/212°F
Blend the sugar in the food processor for 1-2 minutes or until it's powdery and superfine.
Add a tiny pinch of salt to the egg whites and start mixing with the whisk attachment on medium speed.
Once the egg whites are frothy (about 1 minute) add ⅕ of the sugar and continue whisking. Whisk for about 2 minutes then add the second fifth of the sugar.
Continue mixing until all parts the sugar have been added. Continue mixing until you cannot see any grains of sugar in the mixture and stiff peaks have formed.
Stop the mixer and remove the bowl. Add the cornstarch and cinnamon and carefully mix with a spatula, taking care not to knock out any air. Add the lemon juice and continue to mix.
Transfer to a piping bag and cut a large tip at the end.
Place a tiny bit of meringue at the corners of the tray to keep the parchment paper from sticking. Brush the tray with a thin layer of oil. If you're using a Silpat you can skip this step.
Pipe the meringue straight up in 3 tear drop shapes. Pull up quickly at the end to get the curl at the top.
Use a small spoon with an upwards motion to make little arms for the ghost. Push in slightly and pull up quickly with the spoon.
Bake right away for 2-2+½ hours with a spoon holding the door open. Check frequently and turn the tray when they're halfway.
When the meringues are done they will be ideally bright white with a crisp exterior and marshmallowy on the inside. You can use a toothpick to check if they're done. Once finished, turn off the oven and leave them in the oven with the door open to continue drying for about 15 minutes.
Warm up a bit of chocolate in the microwave or over a bain marie. Use a toothpick to paint the face of the ghosts. Enjoy!