'- 1/4 cup (60 gram) unsalted butter, softened- 1/2 cup (100 gram) sugar- 1/4 teaspoon salt- 1 egg (or traditionally, 2 egg whites), room temperature- 1 teaspoon vanilla extract- 60 gram (~ 1/2 cup) all purpose flour

1. Preheat oven to 350 Fahrenheit (180 Celsius). Line 2-3 baking sheets with parchment paper and set aside (or grease with butter generously).2. Cream butter and sugar. In a mixing bowl, cream together butter, sugar, and salt until light and fluffy.3. Add egg and vanilla. Then add egg and vanilla, continue mixing until smooth, about 2-3 minutes. (Notes #1)4. Add flour. Fold in all-purpose flour with a spatula until the batter is smooth.5. Pipe the cookie dough. Transfer cookie dough to a piping bag attached with a plain 1⁄4” tip, pipe into thin strips about 3” long on the prepared baking sheets. Make sure to leave plenty of room (around 2”) since the cookies spread considerably during baking. If you are using half-sheet pans, each pan should fit 24 cookies: 8 in the long direction, and 3 in the short direction. (Notes #2)6. Bake the cookies. Bake in the preheated oven for 8-10 minutes, or until the edges are golden brown.7. Cool and store. Remove the cookies from the oven, cool completely on a wire rack, then store in an air-tight container. The cookies should be fresh for up to 1 week at room temperature.