Test Kitchen Discoveries
Blend both lemon zest and lemon juice in the filling for the brightest flavor. Do take the extra step and strain out the zest, which would mar the otherwise smooth texture. Enrich the curd topping with heavy cream, which tempers the acidity of the lemon and lends a lush texture.
Make sure to line the baking pan with a foil “sling”; otherwise it will be quite tricky to remove the bars without damage.
STEP BY STEP
1. Sprinkle the crust crumbs into the pan and press down gently with a measuring cup to form an even layer.
2. The lemon curd is done when dragging a finger through the curd on the back of a spoon leaves an empty trail behind.
3. Press the curd through a fine-mesh strainer to remove the lemon zest.
4. After pouring the hot curd into the pan, tilt to ensure an even layer.
Most lemon squares are far too sweet and none too lemony. We wanted to reverse that and make a crisp-crusted lemon square with a vibrantly bright lemon flavor.
1 1/4 cups all-purpose flour
1/2 cup confectioners' sugar
Pinch table salt
12 tablespoons cold unsalted butter (1 1/2 sticks), cut into 12 pieces
4 large eggs
3 large egg yolks
1 cup granulated sugar
Pinch table salt
1 tablespoon grated lemon zest plus 2/3 cup juice from 4 lemons
2 tablespoons unsalted butter , cut into 2 pieces
2 tablespoons heavy cream
1. For the crust: Adjust rack to middle position and heat oven to 350 degrees. Line 8-inch-square baking pan with aluminum foil, leaving overhang on all sides.
2. Pulse flour, sugar, and salt in food processor 2 to 3 times. Add butter and pulse until mixture resembles coarse meal (some pea-sized pieces of butter will remain) and will stick together if squeezed into ball, about fifteen 1-second pulses. Sprinkle dough into prepared pan and press in even layer. Bake until light golden brown, 15 to 20 minutes.
3. For the filling: While crust is cooling, whisk eggs, yolks, sugar, and salt together in saucepan. Add zest and juice and cook over medium-low heat, stirring constantly, until thickened and pudding-like, 8 to 10 minutes. Press through fine-mesh strainer into medium bowl. Stir in butter and cream.
4. Pour filling over crust and tilt to spread evenly. Bake until filling is set, about 15 minutes. Cool to room temperature, at least 1 hour, then, using foil overhang, lift bars from pan and cut into 9 squares. Dust with confectioners’ sugar just before serving. (Squares will keep in airtight container in refrigerator for 3 days. Redust with confectioners’ sugar before serving.)
Recipe from America's Test Kitchen e-mail.