Preheat oven to 225°F. Prepare cookie sheets by lining with parchment paper. (Do NOT use pan spray!)
In the bowl of a stand mixer, combine egg whites, cream of tartar, and salt. Using the whisk attachment, whip on medium or medium high until foamy.
As they’re whipping, combine the sugar and DME.
Slowly add in the sugar mixture – a little at a time – and continue whipping until stiff, glossy peaks form and the sugar is completely dissolved. (The mixture shouldn’t feel gritty at all)
Turn off mixer, remove bowl. Gently stir in vanilla extract.
Fit one extra large pastry bag with a large coupler set and tip of your choice – I used used a 4B, large star tip.
Fill with meringue, taking care to avoid air bubbles. I like to tie them off with a little bit of twine, ribbon, or elastic, as it keeps things cleaner.
Use the frosting to pipe small swirls of meringue out onto the prepared cookie sheets. I like to make them just over 2″ in diameter, and leave about 1″ between each little mound.
Bake for 1 hour. Turn the oven off, keep the door closed, and allow them to cool for 2 hours.
Remove from oven and allow to cool fully before transferring to an airtight container.