Pistachio and Sesame Cookies

1. Put the butter into a large bowl. Cream the butter with an electric beater, until creamy and fluffy. Beat in the 1/2 cup sugar, until smooth and creamy. Add the flour and work it in with your hands until it forms a soft dough. If the dough is too dry to work, add a few drops of water (up to 1 tablespoon, always a few drops at a time.)

2. Preheat oven to 340°F. Line a baking sheet with parchment paper. Shape a cherry-size piece of dough into a ball, then flatten it a bit with the palms of your hands. Place on the baking sheet, then repeat with the rest of the dough. Space them about an inch apart on the baking sheet.

3. In a small bowl, mix the ground pistachios, 1/2 tablespoon of sugar and sesame seeds. Add the egg white and beat until incorporated. Brush a few drops of the topping on each cookie (using a brush or the back of a spoon.) Bake for 10 to 15 minutes, checking regularly so the tops are golden but not browned. Remove from oven and let cookies cool completely before serving.

Source: The Illustrated Food and Cooking of Lebanon, Jordan and Syria, by Ghillie Basan.