1/2 cup finely chopped pistachios
3 tablespoons finely chopped rose petals
In a bowl, with an electric mixer, whisk the egg whites at a high speed until slightly frothy. Continue to whisk at a medium-high speed, adding the granulated sugar 1 tablespoon at a time, and then add the powdered sugar in the same fashion. Add the rosewater, food coloring, and salt and turn the mixer to high. Whisk on high until the mixture is glossy and stiff peaks are formed.
Set aside 1 tablespoon of the pistachios and 1 tablespoon of the rose petals for garnish. Fold the remaining pistachios and rose petals into the meringue.
Use 2 spoons to scoop and shape mixture onto parchment, one to scoop, the other to shape the meringues into 1 1/2-inch mounds. The cookies don't need much room between one another, as they don't expand. Dust each meringue with a pinch of the reserved pistachios and rose petals. Bake for 1 hour and 30 minutes, or until hollow-sounding when tapped. Cool on a wire rack and serve that day.
Reprinted with permission from Food with Friends: The Art of Simple Gatherings by Leela Cyd, copyright (c) 2016 by Clarkson Potter