Instructions

1. Cream the butter until it is smooth and velvety. Add the sugar and beat until combined.
2. Beat in the egg white and then the all-purpose flour. Work until the dough is clumpy and just barely combined.
3. Cover the dough and refrigerate it for 15 minutes, until it is less sticky.
4. Once the dough is more workable, roll it into a log about 2 inches thick. Cover it with plastic wrap and refrigerate for at least 2 hours. I rolled my dough into an empty paper towel roll I happened to have, which fit perfectly, though it was a little less than the suggested width. I also refrigerated for 4 hours, which made the dough much more manageable.
5. Preheat the oven to 350F. Line a baking sheet with tin foil or parchment paper.
6. After the dough is thoroughly chilled, slice the cookies with a sharp, clean knife. The sablés should be about a 1/4-inch thick.
7. Space them 2 inches apart on lined baking sheets and bake for 15-17 minutes at 350F, rotating the baking sheets halfway through the baking time. Cool on a wire rack before serving.