Ingredients
Method
Whisk ¾ tsp. Diamond Crystal or ½ tsp. Morton kosher salt, ½ tsp. baking powder, and 3 cups (375 g) all-purpose flour in a small bowl to combine. Using an electric hand mixer or stand mixer on high speed, beat 1¼ cups (2½ sticks) chilled unsalted butter, cut into ½-inch pieces and 1 cup (200 g) sugar in a large bowl until well combined (butter does not need to be fluffy), about 3 minutes. Add 1 large egg, 1 large egg yolk, and 1 tsp. vanilla extract; beat just to combine. Reduce speed to low and gradually add dry ingredients; mix just to combine. Form sugar cookie dough into two ¾"-thick disks; cover each in plastic wrap. Chill at least 2 hours.
Place racks in lower and upper thirds of oven; preheat to 325°. Let 1 disk of dough sit at room temperature until softened slightly, about 5 minutes. Roll out on a lightly floured sheet of parchment paper until about ¼" thick, dusting with flour as needed (if dough gets soft or sticky, chill on parchment until firm). Cut out shapes with floured cookie cutters; transfer cut-out sugar cookies to parchment-lined baking sheets.
Bake cookies, rotating baking sheets halfway through, until edges are golden, 12–16 minutes, depending on size. Transfer baked cookies to wire racks and let cool. Repeat with scraps and remaining dough.
Decorate cooled cookies as desired. Do ahead: Cookie dough can be made 1 month ahead; freeze instead of refrigerating. Cookies can be baked (left undecorated) 2 weeks ahead; wrap tightly and freeze.