Successful lemon bars, with bright lemon flavor, depend on ample amounts of lemon juice and lemon zest. We used four lemons in our filling, along with two whole eggs and seven yolks for thickening. To tame the curd’s pucker power and make it creamy, we added a small dose of heavy cream and some butter. Confectioners’ sugar contributed a tender texture to the crust. We found that it was important to pour the warm filling over a warm crust to ensure that the filling cooked through evenly. If you live in a humid climate, dust the lemon bars with the confectioners’ sugar right before serving. Humidity tends to make the sugar melt and turn splotchy.
Ingredients
Crust
- 1¼ cups (6¼ ounces) all-purpose flour
- ½ cup (2 ounces) confectioners’ sugar
- ½ teaspoon salt
- 8 tablespoons unsalted butter, cut into 8 pieces and softened
Filling
- 2 large eggs plus 7 large yolks
- 1 cup (7 ounces) plus 2 tablespoons granulated sugar
- ¼ cup grated zest plus ⅔ cup lemon juice (4 lemons)
- Pinch salt
- 4 tablespoons unsalted butter, cut into 4 pieces
- 3 tablespoons heavy cream
- Confectioners’ sugar
How to Make It
- Adjust oven rack to middle position and heat oven to 350 degrees. Make foil sling for 8-inch square baking pan by folding 2 long sheets of aluminum foil so each is 8 inches wide. Lay sheets of foil in pan perpendicular to each other, with extra foil hanging over edges of pan. Push foil into corners and up sides of pan, smoothing foil flush to pan, and grease foil. For the Crust
- Process flour, sugar, and salt in food processor until combined, about 3 seconds. Sprinkle butter over top and pulse until mixture is pale yellow and resembles coarse cornmeal, about 8 pulses. Sprinkle mixture into prepared pan and press firmly into even layer using your fingers. Bake until crust starts to brown, about 20 minutes, rotating pan halfway through baking. For the Filling
- Meanwhile, whisk egg and yolks together in medium saucepan. Whisk in granulated sugar until combined, then whisk in lemon zest and juice and salt. Add butter and cook over medium-low heat, stirring constantly, until mixture thickens slightly and registers 170 degrees, about 5 minutes.
- Strain mixture immediately through fine-mesh strainer into bowl and stir in cream. Pour warm lemon curd over hot crust. Bake until filling is shiny and opaque and center jiggles slightly when shaken, 10 to 15 minutes, rotating pan halfway through baking.
- Let bars cool completely in pan, about 2 hours. Using foil overhang, lift bars from pan. Cut into squares, dust with confectioners’ sugar, and serve.
