Make the dough
Position racks in the upper and lower thirds of the oven and heat the oven to 350°F. Line 2 or more cookie sheets with parchment or nonstick baking liners.
Whisk the flour, baking powder, and salt in a medium bowl.
In a stand mixer fitted with the paddle attachment (or in a large mixing bowl with a hand-held electric mixer), beat the butter and sugar on medium speed until light and fluffy, 3 to 4 minutes. Scrape down the bowl and beater with a rubber spatula as needed.
Add the egg and vanilla and continue to mix until well blended, about 1 minute. Reduce the speed to low, add the flour mixture, and mix until well blended, about 1 minute more.
Shape and bake the dough
Turn the dough out onto a lightly floured work surface and gently knead until it’s smooth, with no air pockets. Using a large piece of plastic wrap as an aid, shape the dough into a 12-inch-long, 2-inchwide log. Twist the ends of the plastic to compact and secure the log. To help the dough keep its shape, set it in an empty cardboard paper towel tube that’s been slit lengthwise and freeze until very firm, at least 2 hours. Alternatively, give the log a quarter turn every 15 minutes during the first hour of freezing to keep it from flattening on one side.
Using a sharp, thin knife, slice the dough a scant 1/4 inch thick and arrange the cookies about 1 inch apart on the prepared sheets. If the dough becomes too soft to hold its shape when slicing, refreeze until firm; if it’s too hard to slice, let it sit at room temperature until sliceable.
Bake two sheets at a time, rotating and switching their positions halfway through, until the edges and bottoms of the cookies are golden (or darker brown for chocolate cookies), about 10 minutes. Let the cookies cool on their sheets on wire racks for about 5 minutes and then transfer them to the racks to cool completely.
Serve, decorate, or freeze the cookies.
Make Ahead Tips
You can cover and refrigerate the dough overnight, or freeze the dough log for up to 1 month; thaw in the refrigerator for one hour before slicing and baking.
Baked, undecorated cookies can be frozen in an airtight container for up to 1 month; thaw in the refrigerator before decorating.
Decorated cookies can be kept at room temperature for up to 3 days.
Coffee Dough: Dissolve 1 Tbs. instant espresso or coffee granules in the vanilla paste or extract before adding with the egg.
Almond Dough: Reduce the vanilla paste or extract to 1 tsp. Add 1/2 tsp. pure almond extract and 1/3 cup ( 1-1/2 oz.) finely chopped toasted slivered almonds with the egg.
Chocolate Dough: Reduce the flour to 6-3/4 oz. ( 1-1/2 cups) and add 2 oz. (1/2 cup) unsweetened natural cocoa powder, sifted if lumpy, to the flour mixture. Increase the sugar to 1-1/4 cups.
Lemon Dough: Reduce the vanilla paste or extract to 1 tsp. Add 1-1/2 Tbs. finely grated lemon zest with the egg.
Mint Dough: Reduce the vanilla paste or extract to 1 tsp. Add 1/4 tsp. peppermint extract with the egg.
Orange Dough: Reduce the vanilla paste or extract to 1 tsp. Add 2 Tbs. finely grated orange zest with the egg.
Spice Dough: Add 1-3/4 tsp. ground cinnamon, 3/4 tsp. ground ginger, 1/8 tsp. ground nutmeg, and a pinch of finely ground black pepper to the flour mixture. Use vanilla as directed.
nutrition information (per serving):
Photo: Scott Phillips