Preheat the oven to 350 degrees F. Line cookie sheets with parchment paper or Silpat.
Grind pistachios with all but 2 tablespoons of the sugar in a food processor, leaving some chunks for texture.
Beat the egg whites until stiff peaks form, gradually adding the remaining 2 tablespoons sugar, salt, and cream of tartar. Gently fold the ground pistachio nuts and rose water into the egg whites in three additions, using a large spatula.
Drop by heaping tablespoonfuls (or shape into rounds with your hands), leaving 1-inch between the cookies. Bake until lightly browned, approximately 17 to 20 minutes. Remove from oven and let cool on the baking sheets for a few minutes; transfer to wire racks to cool completely. Store in an airtight container at room temperature.
* Rose Water is distilled from water and roses. It is used heavily in South Asian, West Asian, and Middle Eastern cuisine (especially in sweets). It is usually found in specialty stores (Asian or Indian grocery and spice stores), but some grocery stores now carry it. If you are unable to find culinary essence or rose water, substitute 1 tablespoon fresh-squeezed lemon juice.
Pistachio Rosewater Macaroons Recipe: https://whatscookingamerica.net/Cookie/PistachioMacaroons.htm