Directions

1. Stir together 1 teaspoon sugar, the pistachios, and coconut in a small bowl.
2. Put butter and remaining sugar into the bowl on an electric mixer fitted with paddle attachment. Mix on medium speed until combined. Add egg yolk and vanilla; beat until pale and fluffy, about 2 minutes. Reduce speed to low. Add flour, cardamom, and salt; mix until smooth. Wrap dough in plastic, and refrigerate until firm, about 2 hours.
3. Preheat oven to 350 degrees. Transfer dough to a nonstick baking mat (such as Silpat), or parchment paper. With a floured rolling pin, roll out a 12 by 8-inch rectangle about 1/4 inch thick. Use a pizza wheel to create straight sides, discarding scraps. Carefully transfer mat or paper to a baking sheet. Cut into twenty-four 2-inch squares. Brush with egg white and sprinkle with pistachio mixture.
4. Bake until firm and edges are pale golden brown, 10 to 12 minutes. Remove from oven and run pizza wheel over original cuts. Gently break into individual crackers. Transfer to a wire rack to cool. Cookies can be stored in an airtight container at room temperature up to 3 days.