This is my favorite sugar cookie recipe. The editors at Cooks Illustrated tested countless variations of recipes and tweaked them until they came up with their version of the perfect recipe. For the sugar cookies, they got it exactly right!
Master Recipe for Rolled Butter Cookies
1/2 pound (2 sticks) unsalted butter, softened
1 cup superfine sugar, or granulated sugar processed in food processor for 30 seconds
1/2 teaspoon salt
1 large egg, plus 1 yolk
2 teaspoons vanilla extract
2 1/2 cups all-purpose flour, plus extra for work surface
Either by hand or with electric mixer, cream butter, sugar, and salt until light and fluffy, about 3 minutes with mixer set at medium speed. Add yolk, beat well, then add whole egg and vanilla; continue beating until well incorporated. Add flour; beat at low speed until flour is just mixed in. Divide dough in half and wrap in plastic wrap. Refrigerate until firm, at least 1 hour. (Can be refrigerated up to 2 days or double-wrapped and frozen for 1 month).
Adjust oven racks to upper- and lower-middle positions and heat oven to 375 degrees. Remove one disk of dough from refrigerator and cut in half. Return unused portion of dough to refrigerator.
Lightly flour work surface; roll dough to 1/8 inch thick, using thin metal spatula to loosen dough. Sprinkle surface lightly with flour as needed to keep dough from sticking.
Cut or form dough into desired shapes. Place dough shapes 1/2 inch apart on parchment-lined cookie sheet. Bake, reversing cookie sheets (from top to bottom and back to front) halfway through the baking time, until evenly golden brown, 6 to 8 minutes.
Use thin bladed spatula to immediately transfer cookies to cooling rack. Cool to room temperature. Decorate cooled cookies, if desired, and transfer to airtight container (can be stored up to 3 weeks).