Sablés Bretons

Instructions

1. Prepare the ingredients
   Ensure the butter is at room temperature. Separate the egg yolks from the whites, reserving 4 yolks for the dough and 1 whole egg for the egg wash. Sift together the flour and baking powder in a bowl.
2. Make the dough
   In a large mixing bowl, cream together the butter and sugar until light and fluffy, about 3-4 minutes. Add the egg yolks one at a time, mixing well after each addition. Stir in the vanilla extract and fleur de sel.
3. Combine dry and wet ingredients
   Gradually add the sifted flour and baking powder mixture to the butter mixture, folding gently until just combined. Be careful not to overmix. The dough should be soft but not sticky.
4. Chill the dough
   Form the dough into a disk, wrap in plastic wrap, and refrigerate for at least 1 hour or up to overnight. This helps the flavors develop and makes the dough easier to handle.
5. Shape the cookies
   Preheat the oven to 350°F (175°C) and line baking sheets with parchment paper. Roll out the chilled dough on a lightly floured surface to about 1/4 inch (6mm) thickness. Use a 2-inch (5cm) round cookie cutter to cut out circles.
6. Apply egg wash
   Place the cookies on the prepared baking sheets, spacing them about 1 inch apart. Whisk together the whole egg and milk to make an egg wash. Brush the tops of the cookies with the egg wash, then use a fork to create a crosshatch pattern on top.
7. Bake to golden perfection
   Bake in the preheated oven for 12-15 minutes, or until the edges are golden brown. The centers should remain pale. Rotate the baking sheets halfway through for even baking.
8. Cool and store
   Allow the cookies to cool on the baking sheets for 5 minutes, then transfer to a wire rack to cool completely. Store in an airtight container at room temperature for up to 1 week, or freeze for up to 3 months.