Combine egg whites and cream of tartar. Beat to soft peaks at medium speed.

Switch to high speed and beat to stiff peaks, gradually adding the sugar along the way.

Fold in food coloring to get the color you're looking for.

Preheat the oven to 200°F and prepare a baking tray lined with a silicon mat or a sheet of parchment.

Transfer the meringue to a pastry bag fitted with a large star tip.

Pipe the meringue onto the baking sheet as shown in the video.

Bake for 2 hours, or until the trees are dried through. Turn off the oven, leaving the trees in the oven as it cools.