The tarte au citron is a testament to the French love of simplicity. Made of lemon curd filling in a pâte sablée, it’s topped with meringue and nothing else. This layer cake from Frank Barron of the blog Cake Boy Paris plays up the original with lemon cake layers, Meringue Buttercream, and a tart Lemon Curd center. Decorate with dollops of brûléed meringue for an American take on this pâtisserie staple. Find more recipes from Frank in our 2019 March/April issue!
The Pastry Behind the Cake: Lemon-Basil Tart at Jacques Genin
By Lindsey Tramuta
Jacques Genin’s Lemon-Basil Tart is the source of inspiration behind Frank’s Citron Cake. The general consensus is that Jacques Genin excels at all of the sweet staples. While it’s tough to pick favorites, the initiated know that Jacques’s pastries are worth a special visit, all made to order exclusively in the tea salon at his Marais boutique. The Lemon-Basil Tart in particular has earned a cult following for its balance of sweetness and acidity. “I love the zingy freshness of the lemon-lime and the dollop of fresh curd added on top,” says Frank.
- 1 cup (227 grams) unsalted butter, softened
- 2 cups (400 grams) granulated sugar
- 4 large eggs (200 grams), lightly beaten
- 3 cups (375 grams) sifted all-purpose flour
- 1 tablespoon (15 grams) baking powder
- 1 teaspoon (5 grams) baking soda
- 1 teaspoon (3 grams) kosher salt
- 1¼ cups (300 grams) whole buttermilk
- 6 tablespoons (18 grams) lemon zest (about 2 lemons)
- 1 teaspoon (4 grams) vanilla extract
- Meringue Buttercream (recipe follows)
- Lemon Curd (recipe follows)
- Italian Meringue (recipe follows)
- Preheat oven to 350°F (180°C). Butter and flour 3 (6-inch) round cake pans; line pans with parchment paper.
- In the bowl of a stand mixer fitted with the paddle attachment, beat butter and sugar at medium speed until fluffy, 3 to 4 minutes, stopping to scrape sides of bowl. Add beaten eggs in small increments, beating well after each addition.
- In a medium bowl, sift together flour, baking powder, baking soda, and salt. With mixer on low speed, gradually add flour mixture to butter mixture alternately with buttermilk, beginning and ending with flour mixture, beating just until combined after each addition. Beat in zest and vanilla. Divide batter among prepared pans.
- Bake until a wooden pick inserted in center comes out clean, 25 to 30 minutes. Let cool in pans for 10 minutes. Remove from pans, and let cool completely on wire racks.
- Using a serrated knife, level top of cake layers. Place bottom layer on a cake plate. Fill a pastry bag fitted with a round piping tip with Meringue Buttercream. Pipe a ring of Meringue Buttercream around top edge of cake layer. Using a spoon, fill in ring with Lemon Curd. Top with next cake layer, and repeat with Meringue Buttercream and Lemon Curd. Add final layer, and spread a thin layer of Meringue Buttercream on top and sides of cake to create a crumb coat. Refrigerate for 20 minutes.
- Spread remaining Meringue Buttercream on top and sides of cake. Fill a pastry bag fitted with a round piping tip with Italian Meringue. Pipe dollops of Italian Meringue in varying sizes on top of cake. Using a kitchen torch, brown meringue. Fill a pastry bag fitted with a small round piping tip with remaining Lemon Curd. Pipe tiny droplets of Lemon Curd at base of meringue.
- ½ cup (100 grams) granulated sugar
- 2 tablespoons (30 grams) water
- 2 large egg whites (60 grams)
- 1 cup (227 grams) unsalted butter, softened
- 1½ teaspoons (6 grams) vanilla extract
- In a small saucepan, bring sugar and 2 tablespoons (30 grams) water to a boil over medium heat, stirring occasionally. Cook until mixture registers 238°F (114°C) on an instant read thermometer.
- Meanwhile, in the bowl of a stand mixer fitted with the whisk attachment, beat egg whites at high speed until soft peaks form. With mixer on low speed, add sugar syrup in a slow, steady stream until combined. Increase mixer speed to high, and beat until bowl is cooled to room temperature.
- With mixer on medium speed, add butter, 1 tablespoon (14 grams) at a time. Add vanilla, and increase mixer speed to high; beat until smooth. Use immediately.
- ⅓ cup (67 grams) granulated sugar
- ¼ cup (32 grams) cornstarch
- 1½ teaspoons (1.5 grams) lemon zest
- ¼ cup (60 grams) fresh lemon juice (from about 1½ lemons)
- 1 large egg (50 grams)
- 1 large egg yolk (19 grams)
- 1 tablespoon (15 grams) heavy whipping cream
- ¼ cup (57 grams) unsalted butter, softened
- In the top of a double boiler, whisk together sugar, cornstarch, lemon zest and juice, egg, egg yolk, and cream. Cook over simmering water, whisking constantly, until mixture thickens, 10 to 15 minutes.
- Strain mixture through a fine-mesh sieve into a medium bowl. Add butter, 1 tablespoon(14 grams) at a time, whisking until incorporated. Transfer to a Mason jar to let cool; refrigerate until set.
- ½ cup (100 grams) castor sugar
- 1 tablespoon plus 2 teaspoons (25 grams) water
- ¼ cup (50 grams) egg whites
- In a small saucepan, bring sugar and 1 tablespoon plus 2 teaspoons (25 grams) water to a boil over medium heat, stirring occasionally. Cook until mixture registers 250°F (121°C) on a candy thermometer.
- Meanwhile, in the bowl of a stand mixer with the whisk attachment, beat egg whites at high speed until soft peaks form. With mixer on medium speed, add sugar syrup in a slow, steady stream until combined. Increase mixer speed to high, and beat until bowl is cooled to room temperature. Use immediately.
This is too much batter for 6 in cake rounds. Other than that, it was absolutely delicious. I substituted princess emulsion for vanilla extract in the merengue buttercream. Totally unnecessary but I like that flavor.