1. Process sugars and salt in a food processor until finely ground, about 10 seconds. Add butter, egg yolk, and vanilla, and process until smooth and creamy, 15 seconds. Scrape down sides of bowl, add flour, and pulse until dough forms into a ball.

2. Transfer dough to a lightly floured counter and roll into a 2" diameter log (length will vary based on variation). Wrap tightly with plastic wrap and refrigerate until very firm, at least 2 hours and up to 3 days.

3. Adjust the racks to the upper and lower-middle positions and heat oven to 350 degrees. Slice chilled dough into 1/4"-thick rounds and place 1" apart on 2 parchment-lined baking sheets. Bake until edges are just golden, 12 to 15 minutes, switching and rotating pans halfway through. Let cool 10 minutes before transferring to a wire rack to cool completely.

Source: Hannaford fresh Magazine, November - December 2015