Makes 16 pieces.
Note: Rice flour is in the baking aisle. Bob’s Red Mill is a popular brand. From “Baking Illustrated.”
• 1 3/4 c. all-purpose flour
• 1/4 c. rice flour (or use cornstarch)
• 2/3 c. plus 1 tsp. sugar, divided
• 1/4 tsp. salt
• 16 tbsp. (2 sticks) cold unsalted butter
Preheat oven to 425 degrees. Move an oven rack to the middle position.
Place a circle of parchment paper in a 9-inch tart pan with removable bottom, or in a round cake pan.
In the bowl of an electric mixer, blend the flours, 2/3 cup sugar and salt.
Cut the butter into ½-inch cubes and add to the flour mixture. Mix at low speed for several minutes until the mixture resembles damp crumbs. Do not overmix.
Pour half the mixture into the prepared pan, smooth into an even layer, then firmly press with a juice glass or back of a spoon. Add the rest of the mixture and repeat, pressing firmly.
If using a cake pan, place a baking sheet on top of the pan, then invert. Tap the bottom of the pan until the dough releases, then carefully lift off pan and remove parchment. If the dough cracks a bit, press back together. (If it crumbles a lot, repeat the whole process; for this reason, a tart pan is preferred.)
With a 1½-inch cookie cutter or a sharp knife, cut a circle of dough from the center. Place this nugget on a folded piece of aluminum foil to bake for 20 minutes. Replace cookie cutter in the hole to hold its shape and help conduct heat. (Or use a small ball of crumpled aluminum foil.)
Place pan in the oven and reduce heat to 300 degrees. Bake for 20 minutes.
Remove pan (and tiny cookie) and, using the edge of a spatula, gently score the surface into 16 wedges. If desired, pierce a decorative pattern with a skewer.
Return pan to oven (eat the cookie) and bake an additional 40 minutes.
Sprinkle surface of hot shortbread with remaining 1 teaspoon of sugar, then cool on a wire rack for an hour. Remove from tart pan and cool thoroughly, about 2 more hours.
Cut into wedges with a large knife along scored lines using steady downward pressure. Well-wrapped shortbread can be stored at room temperature for up for one week.
Chocolate-cayenne: Decrease all-purpose flour to 1½ cups, and substitute cocoa for the remaining ¼ cup. Add rice flour, sugar and salt, along with 1 teaspoon espresso powder and 1 teaspoon cayenne pepper. Proceed with the recipe, omitting sprinkle of sugar.
Orange-pistachio: To the flour mixture, add the grated zest of 1 orange and ½ cup fine-chopped pistachios. Proceed with the recipe.
Butterscotch: Substitute brown sugar for the white sugar. Proceed with the recipe. After pressing into the pan, sprinkle with about ½ teaspoon coarse salt. (We used pink Hawaiian.) Omit final sprinkle of sugar.
Nutrition information per serving:
Calories 194 Fat 12 g Sodium 2 mg
Carbohydrates 21 g Saturated fat 7 g Calcium 6 mg
Protein 2 g Cholesterol 31 mg Dietary fiber 0 g
Diabetic exchanges per serving: 1 ½ other carb, 2 ½ fat.