Set up a food processor and combine the pistachios with 1/4 cup of the sugar in its bowl. Process them together until they become a fine crumb and set it aside. In another large bowl, whip up the egg whites with a hand mixer until they start to form soft peaks. Add the remaining 1/2 cup sugar, cinnamon and salt and continue to beat the egg whites until they form stiff peaks. Then add the pistachio crumb, rose water and flour in and beat the mixture together just until combined into a dough. Cover the bowl and set it in the refrigerator to chill for at least an hour.

Once the dough has chilled, pre-heat the oven to 375 and line a sheet tray with a silicone mat. Use a 1.5 inch cookie scoop to scoop perfect little mounds of dough onto the sheet tray. These do not spread much at all, so I squeezed 18 on one sheet with a little space between them. Two sheets of 9 would also have worked! Bake the cookies for about 12-15 minutes, until slightly brown around the edges and baked through. Let them cool for 5 minutes, then transfer them to a rack to finish cooling. Serve them as needed and enjoy! They will keep for days in a sealed container.