Preheat your oven to 215°F. Line a baking sheet with parchment paper and set aside. Begin whisking the egg whites with the whisk attachment on medium low.

Add in the cream of tartar, vanilla, and salt, if using. Increase speed to medium and start adding sugar.

Increase the speed to medium-high. After the whites begin to hold their shape, bump up the mixer to medium-high until they hold firm peaks.

Add gel food coloring or additional flavors, if using.

Fill the piping bag with meringue and pipe out the meringue on a parchment-lined cookie sheet.

Bake for anywhere from 60 to 90 minutes; or until the outside is crisp and the inside is dry, yet chewy. They should feel light and hollow and should easily peel off the parchment paper. Turn the oven off, crack the door open, and let the meringue cool completely in the oven.