You can flavor these any way you crave — I use 1 teaspoon vanilla bean paste, extract would work too, as would lemon, orange or another citrus zest, almond extract, and more. I can’t wait to see what you come up with. To use granulated, superfine, or caster sugar instead of powdered sugar, use half as much. If you’d like to use the semolina flour swap I liked, you’ll want to swap by weight, not volume: Add ¼ cup (45 grams) semolina flour and remove ⅓ cup (45 grams) all-purpose flour.
- 1 cup (230 grams or 8 ounces) unsalted butter, cut into chunks
- ⅔ cup (80 grams) powdered sugar
- 1/2 teaspoon fine sea salt
- Flavoring of choice (see Note)
- 2 ¼ cups (295 grams) all-purpose flour
In a stand mixer: Beat butter, sugar, and salt together, scraping frequently, until butter is soft. Add flavoring of choice and flour, and mix just until combined, scraping down the bowl again. This is the same order as for a hand mixer, but with a hand mixer, you’ll want the butter semi-softened first.
In a food processor: Combine powdered sugar, salt, and flour in the work bowl, pulsing a few times. Add flavoring of choice and butter and pulse several times to chop the butter down into smaller pieces. Then, run the machine until it is fully incorporated, coming together in a smooth mass, 1 to 2 minutes more. Scrape down the bowl a few times for even mixing.
All methods: Add to baking pan in chunks. Use hands to press evenly into the pan, then an offset spatula to smooth the top.
Bake: For 20 minutes, then remove from the oven to cut into shapes. Leave oven on.
Shape the cookies: For the 8-inch square pan, cut into 3 columns (about 2.5 inches wide) in one direction and 8 thin bars (just shy of 1 inch) in the other. Use the back of a wooden skewer (cut method explained explained in the post) to drag across the surface, making slightly indented lines first, then use a very thin, sharp paring knife to cut along these lines to the bottom of the pan. Dock the cookies all over, about 1/3 deep, with the back of the skewer (for bigger dots) or the pointy end (for smaller holes).
For a 9-inch round pan, use a 2 to 3-inch round cookie cutter or glass to cut the center. Then, use the back of a wooden skewer (cut method explained in the post) to gently indent lines like sun rays or the hands of a clock from the inner circle to the outer edge of the cookie so that they’re your desired size wedges. Then use a very thin, sharp paring knife to cut along these lines to the bottom of the pan. Dock the cookies all over, about 1/3 deep, with the back of the skewer (for bigger dots) or the pointy end (for smaller holes).
Finish baking: Return to the oven for another 25 to 35 minutes, until cookies have a deep golden edge but are mostly pale across the top. I find most ovens unreliable (either running hot or cold) at 300 degrees so keep an eye on these in the last 10 to 15 minutes so they don’t overbake.
Let cool in pan, or, if you’re impatient, let them cool for 10 minutes, and then remove them.
Do ahead: Shortbread keeps for 1 week, if not longer, at room temperature. It freezes well too, just wrap it tight.