Citrus Sponge Cake Recipe

Prepare and preheat

Preheat oven to 350°F (175°C). Grease and line an 8-inch (20 cm) round cake pan with parchment paper, leaving an overhang for easy removal.

Dry ingredients

Whisk together the all-purpose flour, baking powder and sea salt in a medium bowl until evenly combined.

Beat eggs and sugar

In a large mixing bowl, combine the 4 large eggs and 1 cup granulated sugar. Using a hand mixer or stand mixer on high speed, beat for 6–8 minutes until the mixture is pale, thick and ribbons fall from the whisk (this aerates the batter to create a light sponge).

Fold in flavor and dry ingredients

Gently fold the lemon zest and vanilla extract into the whipped eggs. Sift the flour mixture over the egg mixture in two additions, folding gently with a spatula after each addition to preserve as much air as possible.

Add milk and butter

Warm the tablespoon of milk and the melted butter slightly (they should be warm, not hot). Drizzle the milk and melted butter in a thin stream into the batter while folding gently until incorporated and smooth. Do not overmix.

Bake

Pour the batter into the prepared pan, smooth the top and bake in the preheated oven for 22–28 minutes, or until the cake is golden and a toothpick inserted into the center comes out clean or with a few moist crumbs. Rotate the pan halfway through baking if your oven has hot spots.

Cool

Let the cake cool in the pan for 10 minutes, then use the parchment overhang to lift it onto a wire rack. Cool completely before layering with lemon curd (about 1–1.5 hours). While cake cools, prepare the lemon curd and crème anglaise.

Combine and heat

In a medium, heavy-bottomed saucepan, whisk together the 1 cup lemon juice, 1 cup granulated sugar, the 3 whole eggs and 2 egg yolks until smooth and uniform in color.

Cook and thicken

Place the saucepan over medium-low heat. Cook, stirring constantly with a heatproof spatula or wooden spoon and making sure to scrape the bottom and corners, until the mixture thickens and reaches about 170–175°F (77–80°C) and coats the back of the spoon. This takes roughly 8–12 minutes. Do not let it boil.

Finish with butter and zest

Remove the curd from the heat and immediately whisk in the cold cubed butter a few pieces at a time until fully incorporated and the curd is glossy and smooth. Stir in the 1 tablespoon lemon zest. If there are any bits of cooked egg, strain the curd through a fine-mesh sieve into a clean bowl.

Cool and chill

Press plastic wrap directly onto the surface to prevent a skin from forming. Let cool to room temperature, then chill in the refrigerator for at least 1 hour to firm up. Lemon curd will further thicken as it cools.

Infuse milk and cream

In a medium saucepan, combine 1 cup whole milk and 1 cup heavy cream. Add the split vanilla bean and scraped seeds (or 1 teaspoon vanilla extract). Warm the mixture over medium heat until it just begins to steam and small bubbles form around the edge (do not boil). Remove from heat and let steep for 10 minutes if using a bean for stronger flavor; if using extract, skip steeping.

Whisk yolks and sugar

While the milk is steeping, whisk together the 4 egg yolks, 1 tablespoon granulated sugar and a pinch of salt in a medium bowl until the mixture lightens slightly.

Temper and thicken

Slowly drizzle about a half cup of the warm milk mixture into the yolks while whisking constantly to temper. Then gradually pour the tempered yolk mixture back into the saucepan with the remaining milk, stirring continuously. Place the saucepan over low heat and cook, stirring constantly with a wooden spoon or spatula, until the custard thickens enough to coat the back of a spoon and reaches 170–175°F (77–80°C). Do not allow it to boil or the yolks will curdle.

Finish and chill

Remove from heat, strain the crème anglaise through a fine-mesh sieve into a clean bowl to remove the vanilla pod and any coagulated bits. If desired, stir in 1/2 teaspoon vanilla extract for extra aroma. Cover with plastic wrap pressed to the surface and chill until cold, at least 1 hour. The sauce will thicken slightly as it cools.

Layer or serve

If serving as a layered cake: slice the cooled sponge horizontally into two even layers with a serrated knife. Spread half of the chilled lemon curd evenly over the bottom layer, place the top layer back on, and spread more curd on top if desired. Alternatively, serve slices of sponge with a generous spoonful of lemon curd on top.

Plate with crème anglaise

Spoon a pool of chilled vanilla bean crème anglaise onto each dessert plate and place a slice of the lemon-curd-topped sponge on top or beside the pool. Drizzle additional curd lightly over the cake if desired.

Garnish

Dust with powdered sugar if using, and garnish with thin lemon slices or candied peel and a small mint leaf. Serve immediately so the cake remains tender and the crème anglaise cold.