1teaspoonfinely grated fresh tangerine or orange zest
Gel-paste food coloringin orange
Instructions
Preheat oven to 200 degrees. Whisk egg whites and sugar together in a heatproof bowl. Add the vanilla bean seeds. Set the bowl over a pot of simmering water, and stir until sugar dissolves and mixture is warm, about 3 minutes. Add cream of tartar and salt.
Beat with a mixer on medium-high speed until stiff, glossy peaks form and meringue is mostly cooled, about 7 minutes. Beat in zest. Check frequently to ensure the meringue is not over-beaten.
Using a small paintbrush, paint 3 vertical stripes of food coloring inside a pastry bag fitted with a 1/2-inch round tip (Ateco #805). Space the lines equally around the bag for most attractively striping. Carefully fill the bag with meringue, taking care to push the meringue straight down to the tip without smearing the food coloring. Pipe 1 3/4-inch circular shapes (they don't need to be perfect rounds) 2 inches apart on 2 parchment-lined baking sheets. As you finish piping each cookie, apply less pressure to pastry bag, and swirl the tip off in a circular motion.
Bake the meringue cookies until crisp on the outside but still soft inside, about 1 hour 15 minutes. Remove from the oven and let set for about 10 minutes. Gently transfer the meringues to a wire rack and allow to cool completely.