These crispy confections are brimming with kid appeal, and they're easy to make by the trayful for holiday parties.
Heat the oven to 200º F. With an electric mixer, beat the egg whites until soft peaks start to form. Beating all the while, add the cream of tartar and vanilla extract, then slowly add the 1/2 cup of sugar. Continue to beat until the peaks stiffen.
Spoon the meringue into a quart-size plastic bag. Snip off a corner and pipe 2 dozen 1 1/2-inch-tall Santa hat triangles onto a parchment-lined baking sheet (you should have about 1/4 of the meringue left).
Sprinkle the triangles with the red sugar, then use the remaining meringue to give each one a pom-pom and trim. Bake the hats until they're hard but not browned, about 1 hour and 20 minutes. Turn off the oven and leave the hats in it for an hour to crisp before removing.