makes 2-3 dozen cookies
3/4 tsp Kosher Salt
1/2 tsp baking powder
3 Cups all-purpose flour, plus more for rolling
1-1/4 Cups (2-1/2 sticks) chilled unsalted butter, cut into 1/2″ pieces
1 Cup sugar
1 large egg
1 large egg yolk
1 tsp Vanilla Extract or Vanilla Paste
Using an electric mixer on high speed, beat together the butter and sugar until well combined (butter does not need to be fluffy), about 3 minutes. Add egg, egg yolk, and vanilla to butter-sugar mixture; beat just to combine. Reduce mixer speed to low and gradually add dry ingredients; mix just to combine. Form dough into two 3/4″-thick “logs”; wrap in plastic. Chill at least 2 hours.
Place racks in lower and upper thirds of oven; preheat to 325°F. Whisk salt, baking powder, and 3 Cups flour in a small bowl.
Let 1 log of cookie dough sit at room temperature until softened slightly, about 5-10 minutes. Roll out dough on a lightly-floured sheet of parchment paper until about 1/4″ thick, dusting with flour as needed (if dough gets soft or sticky, pop into the refrigerator and chill on parchment until dough firms up again).
Cut out cookies with floured cookie cutters; transfer to parchment-lined baking sheets.
Repeat sugar cookie roll-out and cut-out with leftover dough scraps and remaining dough “log.”
Bake cookies in 325F oven, rotating baking sheets halfway through, until edges are golden, 12–16 minutes, depending on cookies’ size (bigger cookies will take longer to bake, smaller ones will be quicker).
Remove baking sheets from oven, and transfer cookies to wire racks and allow to cool completely.
Decorate cooled cookies as desired.
MAKE AHEAD: Cookie dough can be made up to 1 month ahead; wrap dough and freeze instead of chilling. Cookies can be baked (if left undecorated) up to 2 weeks ahead; wrap tightly and freeze. Allow several hours for frozen dough to thaw before using.