Ah, lemon bars. No other cookie is so sure to disappoint. Remember that warning song from Peter, Paul, and Mary: “But the fruit of the poor lemon tree is impossible to eat.”
If not impossible, then distinctly unpleasant. Lemon bars come to you usually dry to the point of desiccation, cracked like the Mojave desert flour, and with the sweetness of a kiss from that girl of your first divorce. After the divorce. Bakeries butcher lemon bars, and making them at home is a chore.
Well, half the problem is now solved, thanks to the cookbook Flour by Joanne Chang. You can make the world’s best lemon bars at home. It is a bit of a chore, I admit, but there’s a sharp reason: you’re going to be using a dozen eggs, over a dozen lemons, nearly 3 sticks of butter, and lots of sugar. Oh, yeah, heavy cream, too. If you are Catholic, after you make these, you need to go to confession. Just slip the priest one of the cookies, though, and you penance will be light. In fact, all you may to do is supply him with the recipe.
The secret to this recipe is the multi-staging. A wonderful shortbread is quick baked. Then a very rich lemon curd is prepared and thickly poured over the shortbread, and the whole thing is further baked to perfection. Traditional lemon bars simply have a lemon mixture that is poured over the shortbread and then cooked only through the baking process. Here, the lemon portion is a completely cooked curd, so it can be piled high and deep and has achieved full flavor.
Be prepared to give out this recipe to any and all who taste it. Regardless of religious affiliation.
Lemon Lust Bars
Yield: 18 very sizable portions of lemon magic
For the Shortbread:
- 1 cup (2 sticks/228 grams) unsalted butter, at room temperature
- 6 tablespoons (75 grams) granulated sugar
- 2 tablespoons confectioners’ sugar
- 1 egg yolk
- 1 teaspoon vanilla extract
- 1 cup (140 grams) unbleached all-purpose flour
- 1 cup (120 grams) cake flour
- ½ teaspoon baking powder
- ½ teaspoon kosher salt
For the Lemon Curd:
- 2 cups plus 2 tablespoons (500 grams) fresh lemon juice (14 to 16 lemons)
- 1/2 cup (1 stick/114 grams) unsalted butter
- ½ cup (60 grams) heavy cream
- 8 eggs
- 4 egg yolks
- 2 cups (400 grams) granulated sugar
- 1 teaspoon kosher salt
- 1 teaspoon vanilla extract
To make the shortbread: Using a stand mixer fitted with the paddle attachment (or a handheld mixer or a wooden spoon), cream together the butter, granulated sugar, and confectioners’ sugar on medium speed for about 5 minutes, or until light and fluffy. (This step will take about 10 minutes if using a handheld mixer or a spoon.) Stop the mixer a few times and use a rubber spatula to scrape the sides and bottom of the bowl and the paddle to release any clinging butter or sugar. Beat in the egg yolk and vanilla on medium speed for 2 to 3 minutes, or until thoroughly combined. Scrape the bowl and paddle again with a rubber spatula to make sure the egg yolk is thoroughly incorporated.
In a medium bowl, sift together the all-purpose flour, cake flour, baking powder, and salt. On low speed (or with the wooden spoon), slowly add the flour mixture to the butter-sugar mixture and then mix for about 15 seconds, or until the flour mixture is totally incorporated and the dough is evenly mixed. Stop the mixer and scrape the bowl again to make sure all of the flour mixture is thoroughly incorporated.
Scrape the dough out onto a sheet of plastic wrap and wrap the dough in the plastic wrap, pressing down to form a disk 6 to 7 inches in diameter and 1 inch thick. Refrigerate the dough about 30 minutes, or until it has firmed up but is still somewhat pliable. (At this point, the can be stored in the refrigerator for up to or in the freezer for up to 1 month. If the dough is frozen, thaw it overnight in the refrigerator then let it sit at room temperature for about 20 minutes before using.)
To make the lemon curd: While the dough is chilling. in a medium nonreactive saucepan, combine the lemon juice, butter, and cream. Place over medium-high heat and heat to just below a boil. Meanwhile, in a medium heatproof bowl, whisk together the eggs and egg yolks until blended. Slowly whisk in the granulated sugar until combined. Remove the lemon juice mixture from heat and gradually whisk a little of it into the egg mixture. Continue whisking the hot liquid into the eggs, a little at a time, until all of it has been incorporated.
When all of the lemon juice mixture has been incorporated, return the contents of the bowl to the saucepan, and return the saucepan to medium heat. Cook, stirring continuously with a wooden spoon and making sure to scrape the bottom of the pan frequently to prevent the eggs from scrambling, for 5 to 8 minutes, or until the mixture thickens and coats the spoon thickly. To test, draw your finger along the back of the spoon; the curd should hold the trail for a second or two before it fills.
Remove the lemon curd from the heat and strain through a fine-mesh sieve into a medium bowl or pitcher. Whisk in the salt and vanilla. (The lemon curd can be made up to 4 days in advance and stored in an airtight container in the refrigerator. If using chilled curd, add 5 to 6 minutes to the baking time.
Position a rack in the center of the oven, and heat the oven to 350 degrees F.
Lightly flour the dough disk and two large sheets of parchment paper. Place the dough between the sheets of parchment, and roll it out into a rectangle 9 by 11 inches and about ¼ inch thick. Carefully peel off the top sheet of parchment. (Place the whole thing in the fridge for a few minutes if the dough sticks to the parchment.) Transfer the bottom sheet of parchment with the dough to a 9-by-11-inch baking pan or baking dish with at least 2-inch-high sides. Press the dough to fit the bottom of the pan, and allow the parchment to come up the sides of the pan. The dough needs to be about the same thickness all around, but it does not have to be smooth.
Bake for about 20 minutes, or until the shortbread is light brown—about the same color as maple wood. Remove from the oven (leave the over set at 350 degrees F), pour the lemon curd on top, and smooth the filling evenly over the shortbread with a rubber spatula.
Bake for another 15 to 20 minutes, or until the curd has set and jiggles like firm Jell-O. Let cool to room temperature in the pan on a wire rack, then refrigerate for at least 4 hours or up to overnight to allow the curd to set. If refrigerating overnight, lightly drape plastic wrap over the top to keep any refrigerator smells from seeping into your lemon bars.
Gently tug the parchment on all sides to loosen the shortbread from the pan, then slide it out onto a cutting board. Trim the edges of the shortbread, then cut into 18 bars.
The bars can be stored in an airtight container in the refrigerator for up to 2 days.
Source: Flour by Joanne Chang