Preheat your oven to 225°F (107°C) and line a baking sheet with parchment paper.

In a clean mixing bowl, beat the room-temperature egg whites on medium speed until foamy, then add cream of tartar.

Gradually increase mixer speed to high and add sugar one tablespoon at a time, beating until stiff peaks form.

Gently fold in vanilla extract and gel food coloring without deflating the meringue.

Transfer the meringue mixture into a piping bag and pipe small swirls onto the prepared baking sheet.

Optionally, sprinkle with edible sprinkles before baking.

Bake the cookies for 60 minutes, then turn off the oven and leave them inside for an additional 60 minutes.

Cool completely on the baking sheet before transferring to an airtight container if not serving immediately.