Bright Lemon Layer Cake with Silky Lemon Buttercream

Fresh Lemon Juice and Zest

Bottled lemon juice has a flat, metallic taste. Use fresh lemons for both the juice and zest. One large lemon yields about 3 tablespoons of juice and 1 tablespoon of zest. For this recipe, you'll need about 6 lemons total.

Step-by-Step Method

Make the lemon curd first. It needs time to chill and set. Combine lemon juice, zest, sugar, and egg yolks in a small saucepan. Cook over medium-low heat, stirring constantly with a heatproof spatula. The curd is ready when it reaches 170°F (77°C) on an instant-read thermometer and thickly coats the spatula. Stir in the butter until smooth, then strain through a fine-mesh sieve. Press plastic wrap directly onto the surface to prevent a skin from forming, and refrigerate.

Prepare the pans and preheat the oven. Grease three 8-inch round pans, line the bottoms with parchment, and dust with flour. This ensures the layers release cleanly.

Reverse-cream the dry ingredients and butter. In the bowl of a stand mixer with the paddle attachment, combine the cake flour, sugar, baking powder, and salt. Mix on low for 30 seconds. Add the butter pieces one at a time, mixing until the mixture looks like damp sand with no visible butter lumps. This takes about 2 minutes.

Add the wet ingredients. Whisk the eggs, milk, lemon zest, lemon juice, and vanilla together in a separate bowl. With the mixer on low, add the wet mixture in three additions, scraping down the bowl after each. Mix just until smooth — about 30 seconds total. Overmixing at this stage will toughen the cake.

Bake. Divide the batter evenly among the prepared pans (about 380g per pan). Bake at 350°F (175°C) for 22-25 minutes. The cakes are done when a toothpick inserted in the center comes out clean or with a few moist crumbs, and the edges start to pull away from the pans. Cool in the pans for 10 minutes, then turn out onto a wire rack to cool completely.

Make the lemon buttercream. Beat the room-temperature butter on medium-high for 3 minutes until pale and creamy. Gradually add the sifted powdered sugar, then the lemon juice, zest, heavy cream, and salt. Beat for another 2-3 minutes until light and fluffy. If the frosting seems too soft, refrigerate for 10 minutes before using.

Assemble the cake. Place one layer on a serving plate. Spread half the chilled lemon curd over the top, leaving a ½-inch border. Repeat with the second layer and the remaining curd. Top with the third layer. Apply a thin crumb coat of buttercream all over the cake, then refrigerate for 15 minutes. Finish with the final coat of buttercream, smoothing the sides with an offset spatula and creating swirls on top if desired.

Slice and serve. For the cleanest slices, refrigerate the finished cake for at least 30 minutes. Use a sharp serrated knife and wipe it clean between cuts. Let slices sit at room temperature for 10 minutes before serving to soften the buttercream.