Preheat your oven to 225°F (105°C) and line a large or two regular-sized baking sheets with parchment paper ans set aside.
In a clean, grease-free bowl, combine 4 egg whites, ½ teaspoon cream of tartar, and ⅛ teaspoon salt.
Using a mixer on low, beat until foamy.
Gradually increase the speed to high, adding 1 tablespoon of sugar at a time until 1 cup (200g) of sugar is fully incorporated and dissolved.
Continue beating until stiff, shiny peaks form.
Mix in 1 teaspoon vanilla extract and, if desired, food coloring or other extracts.
Transfer the mixture into a piping bag fitted with a large star tip.
Pipe the meringue onto the prepared baking sheets.
Bake for 1 hour, then turn off the oven and let the cookies cool inside without opening the door (1-2 hours).
Store in an airtight container, away from heat and moisture.