Preheat your oven to a gentle 225°F (110°C) and line a baking sheet with parchment paper.

In a clean mixing bowl, beat egg whites on medium speed until foamy.

Add cream of tartar and continue to beat until soft peaks form.

Gradually add granulated sugar, one tablespoon at a time, until stiff peaks form.

Stir in vanilla extract and a few drops of green food coloring until the desired color is reached.

Transfer meringue to a piping bag fitted with a star tip and pipe small tree shapes onto the prepared baking sheet.

Bake for about 1.5 hours, or until meringues are fully dried and lift off the parchment easily.

Let meringues cool completely before decorating with edible glitter, if desired.