1. Preheat the oven to 200 degrees F.
2. Line a baking sheet with parchment paper.
3. Place egg whites and salt in the stand mixer and mix at medium speed until frothy.
4. Add cream of tartar and mix at medium high speed.
5. Beat in sugar, 1 tbsp at a time. Tip: this step is very important, do not add all the sugar at one time, add it in slowly.
6. Add in vanilla extract and mix.
The meringue will start to become stiff with peaks. To check if it is ready, roll a pinch of the meringue mixture between your thumb and finger and feel for any gritty sugar. If there is any present, continue to beat the meringue until it is gone and stiff peaks form.
7. Prep a large piping bag by snipping the end and inserting a large round piping tip. Fold the pastry bag over and place inside of a glass or jar. Fill the bag with the meringue.
Tip: I like to use a 1A piping tip to get the best ghost shape.
8. Squeeze out any air bubbles and twist the top of the bag.
9. Hold the pastry bag straight up and down on the pastry sheet and swirl it around from the center in a circular motion, gently pulling away when you have reached your desired height and size. Create a ghost shape by moving the piping bag, not the cookie tray.