Welcome to Bon Appétit Bake Club, a community of curious bakers. Each month senior Test Kitchen editors Jesse Szewczyk and Shilpa Uskokovic share a must-make recipe and dive deep on why it works. Come bake and learn with us—and don’t forget to join the Bake Club Group chat over on Substack.
A whole lemon—pith, skin, flesh, and all—is a powerful thing. When used correctly, that power can be harnessed for good, heightening the citrus fruit’s bright, piercing notes to soaring new heights. Here, classic lemon bars call upon the brute strength of two whole lemons to embolden the custard with a Lemonhead-like flavor. The lemons are chopped up and blended into pulpy submission along with added juice. (Organic lemons are ideal here, but a good scrubbing of conventional ones will also work.) Blending extracts all of the precious oils from the peels, imbuing the juice with another dimension of lemon flavor. It’s sweet, sour, a touch bitter, and delightfully puckery.
Straining the mixture ensures that the custard layer is free of any lumps that might get in the way of its silky texture; pairing that juice with a can of sweetened condensed milk balances not only the bite, but adds a delightful creaminess akin to a Key lime pie. (Extra credit if you turn those leftover egg whites into a meringue topping.) An added bonus? The whole thing (including the shortbread) can be whipped up by hand without the need for a mixer.
Read More: Drop What You're Doing and Make Bake Club's Lemon Bars
Recipe information
Total Time
1 hour 30 minutes (plus chilling)
Yield
Makes 16
Ingredients
Shortbread
¾
½
2
1
1½
1½
½
Lemon Curd and Assembly
2
1
5
1
¾
Need to make a substitution?
Preparation
Shortbread
Step 1
Place a rack in middle of oven; preheat to 350°. Coat an 8x8" baking pan with nonstick vegetable oil spray and line with parchment paper, leaving overhang on all sides. Whisk together ¾ cup (1½ sticks) unsalted butter, room temperature, ½ cup (55 g) powdered sugar, 2 Tbsp. granulated sugar, 1 Tbsp. vanilla extract, and 1½ tsp. Diamond Crystal or 1 tsp. Morton kosher salt until smooth and powdered sugar is dissolved. Add 1½ cups (188 g) all-purpose flour and ½ tsp. baking powder and mix with a rubber spatula until a soft dough forms and no pockets of unincorporated flour remain. (Don’t undermix; you want to form some gluten in this shortbread. Mix at least 30 seconds.) Transfer dough to prepared pan and, using an offset spatula lightly coated with nonstick spray, spread into an even layer, working all the way to the edges.
Step 2
Bake shortbread until golden brown on top, 33–40 minutes. Let cool 5 minutes. (Set a timer; you don’t want to go longer. The crust needs to be warm when you add lemon mixture.) Reduce oven temperature to 325°.
Lemon Curd and Assembly
Step 3
While the crust is baking, cut 2 medium lemons into about 1" pieces; remove seeds. Transfer to a blender and add 1 cup fresh lemon juice; blend until a pulpy consistency. Strain through a fine-mesh sieve into a large bowl, pressing down on pulp with your hands to extract as much juice as possible. Add 5 large egg yolks, one 14-oz. can sweetened condensed milk, and ¾ tsp. Diamond Crystal or ½ tsp. Morton kosher salt and whisk to combine. Set lemon mixture aside.
Step 4
As soon as timer for crust goes off, pour reserved lemon mixture over it. Bake until lemon curd is set but still jiggles slightly when gently shaken, 18–24 minutes. Let lemon bar cool, then cover and transfer to refrigerator. Chill at least 4 hours and up to 12 hours.
Step 5
Using parchment paper overhang, lift lemon bar from pan and transfer to a cutting board. Dust with powdered sugar if desired and cut into 16 squares.